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    <title>CTET Paper 2 - विज्ञान एवं शिक्षाशास्त्र असाइनमेंट जनरेटर</title>
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        <h1 id="mainTitle">CTET Paper 2</h1>
        <p id="mainSubtitle">विज्ञान एवं शिक्षाशास्त्र (Science and Pedagogy) असाइनमेंट जनरेटर</p>
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            <h2 class="section-title" id="startTitle">विज्ञान एवं शिक्षाशास्त्र असाइनमेंट जनरेटर</h2>
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<script>
    const { jsPDF } = window.jspdf;
    
    // =====================================================
    // BILINGUAL QUESTIONS DATABASE (21 TOPICS: 11 Science + 10 Pedagogy)
    // =====================================================
    const questionBank = {};

    // Helper to add questions
    function addQuestions(topicKey, enQ, hiQ) {
        if (!questionBank[topicKey]) questionBank[topicKey] = { en: { level1: [], level2: [], level3: [] }, hi: { level1: [], level2: [], level3: [] } };
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        hiQ.forEach((q, idx) => {
            const levelKey = levels[idx] || 'level1';
            questionBank[topicKey].hi[levelKey].push(q);
        });
    }

    // ----- SCIENCE TOPICS (11) -----
    // 1. Food
    addQuestions('भोजन',
        [
            { question: "Which nutrient provides energy to the body?", options: ["Carbohydrates", "Proteins", "Vitamins", "Minerals"], answer: "A" },
            { question: "Which vitamin is produced by sunlight?", options: ["Vitamin D", "Vitamin A", "Vitamin C", "Vitamin B"], answer: "A" },
            { question: "Which disease is caused by deficiency of Vitamin C?", options: ["Scurvy", "Rickets", "Beriberi", "Anaemia"], answer: "A" }
        ],
        [
            { question: "शरीर को ऊर्जा किस पोषक तत्व से मिलती है?", options: ["कार्बोहाइड्रेट", "प्रोटीन", "विटामिन", "खनिज"], answer: "A" },
            { question: "सूर्य के प्रकाश से कौन सा विटामिन बनता है?", options: ["विटामिन D", "विटामिन A", "विटामिन C", "विटामिन B"], answer: "A" },
            { question: "विटामिन C की कमी से कौन सा रोग होता है?", options: ["स्कर्वी", "रिकेट्स", "बेरीबेरी", "अरक्तता"], answer: "A" }
        ]
    );

    // 2. States of Matter
    addQuestions('द्रव्य की अवस्थाएँ',
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            { question: "Which is not a state of matter?", options: ["Energy", "Solid", "Liquid", "Gas"], answer: "A" },
            { question: "The process of changing from liquid to gas is called:", options: ["Evaporation", "Condensation", "Melting", "Freezing"], answer: "A" },
            { question: "Which state of matter has definite shape and volume?", options: ["Solid", "Liquid", "Gas", "Plasma"], answer: "A" }
        ],
        [
            { question: "द्रव्य की अवस्था कौन नहीं है?", options: ["ऊर्जा", "ठोस", "द्रव", "गैस"], answer: "A" },
            { question: "द्रव से गैस में बदलने की प्रक्रिया क्या कहलाती है?", options: ["वाष्पीकरण", "संघनन", "गलन", "जमना"], answer: "A" },
            { question: "द्रव्य की किस अवस्था का आकार और आयतन निश्चित होता है?", options: ["ठोस", "द्रव", "गैस", "प्लाज्मा"], answer: "A" }
        ]
    );

    // 3. Daily Use Substances
    addQuestions('दैनिक उपयोगी पदार्थ',
        [
            { question: "Which substance is used to neutralize acidity?", options: ["Baking soda", "Salt", "Sugar", "Vinegar"], answer: "A" },
            { question: "Soap is made by reaction of fat with:", options: ["Sodium hydroxide", "Hydrochloric acid", "Sulfuric acid", "Nitric acid"], answer: "A" },
            { question: "Which is a preservative used in food?", options: ["Salt", "Sugar", "Vinegar", "All of these"], answer: "D" }
        ],
        [
            { question: "अम्लता को दूर करने के लिए किस पदार्थ का उपयोग किया जाता है?", options: ["बेकिंग सोडा", "नमक", "चीनी", "सिरका"], answer: "A" },
            { question: "साबुन वसा की किसके साथ प्रतिक्रिया से बनता है?", options: ["सोडियम हाइड्रॉक्साइड", "हाइड्रोक्लोरिक अम्ल", "सल्फ्यूरिक अम्ल", "नाइट्रिक अम्ल"], answer: "A" },
            { question: "भोजन में परिरक्षक के रूप में किसका उपयोग होता है?", options: ["नमक", "चीनी", "सिरका", "इन सभी का"], answer: "D" }
        ]
    );

    // 4. Living World
    addQuestions('सजीव जगत',
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            { question: "Which organelle is known as the powerhouse of the cell?", options: ["Mitochondria", "Ribosome", "Golgi body", "Nucleus"], answer: "A" },
            { question: "The process of photosynthesis occurs in:", options: ["Chloroplasts", "Mitochondria", "Nucleus", "Ribosomes"], answer: "A" },
            { question: "Which is the smallest unit of life?", options: ["Cell", "Tissue", "Organ", "Organism"], answer: "A" }
        ],
        [
            { question: "किस कोशिकांग को कोशिका का पावर हाउस कहा जाता है?", options: ["माइटोकॉन्ड्रिया", "राइबोसोम", "गॉल्जी बॉडी", "केन्द्रक"], answer: "A" },
            { question: "प्रकाश संश्लेषण की प्रक्रिया कहाँ होती है?", options: ["हरितलवक में", "माइटोकॉन्ड्रिया में", "केन्द्रक में", "राइबोसोम में"], answer: "A" },
            { question: "जीवन की सबसे छोटी इकाई क्या है?", options: ["कोशिका", "ऊतक", "अंग", "जीव"], answer: "A" }
        ]
    );

    // 5. Human Physiology
    addQuestions('मानव कार्यकी',
        [
            { question: "Which organ pumps blood in the human body?", options: ["Heart", "Liver", "Kidney", "Lungs"], answer: "A" },
            { question: "The function of the kidney is:", options: ["Filter blood", "Digest food", "Pump blood", "Exchange gases"], answer: "A" },
            { question: "Which system helps in breathing?", options: ["Respiratory system", "Digestive system", "Circulatory system", "Nervous system"], answer: "A" }
        ],
        [
            { question: "मानव शरीर में रक्त पंप करने वाला अंग कौन है?", options: ["हृदय", "यकृत", "गुर्दा", "फेफड़े"], answer: "A" },
            { question: "गुर्दे का कार्य क्या है?", options: ["रक्त को छानना", "भोजन पचाना", "रक्त पंप करना", "गैसों का आदान-प्रदान"], answer: "A" },
            { question: "साँस लेने में कौन सा तंत्र सहायक है?", options: ["श्वसन तंत्र", "पाचन तंत्र", "परिसंचरण तंत्र", "तंत्रिका तंत्र"], answer: "A" }
        ]
    );

    // 6. Microorganisms
    addQuestions('सूक्ष्मजीव',
        [
            { question: "Which is not a microorganism?", options: ["Earthworm", "Bacteria", "Virus", "Fungi"], answer: "A" },
            { question: "Which microorganism causes malaria?", options: ["Plasmodium", "Virus", "Bacteria", "Fungi"], answer: "A" },
            { question: "Which microorganism is used in making bread?", options: ["Yeast", "Bacteria", "Virus", "Fungi"], answer: "A" }
        ],
        [
            { question: "सूक्ष्मजीव कौन नहीं है?", options: ["केंचुआ", "जीवाणु", "विषाणु", "कवक"], answer: "A" },
            { question: "मलेरिया किस सूक्ष्मजीव से होता है?", options: ["प्लाज्मोडियम", "विषाणु", "जीवाणु", "कवक"], answer: "A" },
            { question: "रोटी बनाने में किस सूक्ष्मजीव का उपयोग होता है?", options: ["यीस्ट", "जीवाणु", "विषाणु", "कवक"], answer: "A" }
        ]
    );

    // 7. Moving Objects & Applications
    addQuestions('गतिमान वस्तुएँ एवं उनके अनुप्रयोग',
        [
            { question: "Force is measured in:", options: ["Newton", "Joule", "Watt", "Pascal"], answer: "A" },
            { question: "Which law states that action and reaction are equal?", options: ["Newton's Third Law", "Newton's First Law", "Newton's Second Law", "Law of Inertia"], answer: "A" },
            { question: "The SI unit of speed is:", options: ["m/s", "km/h", "m/min", "cm/s"], answer: "A" }
        ],
        [
            { question: "बल को किस इकाई में मापा जाता है?", options: ["न्यूटन", "जूल", "वाट", "पास्कल"], answer: "A" },
            { question: "कौन सा नियम बताता है कि क्रिया और प्रतिक्रिया बराबर होती है?", options: ["न्यूटन का तीसरा नियम", "न्यूटन का पहला नियम", "न्यूटन का दूसरा नियम", "जड़त्व का नियम"], answer: "A" },
            { question: "चाल की SI इकाई क्या है?", options: ["m/s", "km/h", "m/min", "cm/s"], answer: "A" }
        ]
    );

    // 8. How Things Work
    addQuestions('चीजें कैसे काम करती हैं?',
        [
            { question: "A lever is an example of:", options: ["Simple machine", "Complex machine", "Compound machine", "No machine"], answer: "A" },
            { question: "The fulcrum is the:", options: ["Fixed point of a lever", "Force applied", "Load", "Effort"], answer: "A" },
            { question: "Which is not a simple machine?", options: ["Engine", "Lever", "Pulley", "Inclined plane"], answer: "A" }
        ],
        [
            { question: "उत्तोलक किसका उदाहरण है?", options: ["सरल मशीन", "जटिल मशीन", "संयुक्त मशीन", "कोई मशीन नहीं"], answer: "A" },
            { question: "आधार बिंदु क्या होता है?", options: ["उत्तोलक का स्थिर बिंदु", "लगाया गया बल", "भार", "प्रयास"], answer: "A" },
            { question: "सरल मशीन कौन नहीं है?", options: ["इंजन", "उत्तोलक", "घिरनी", "झुका हुआ तल"], answer: "A" }
        ]
    );

    // 9. Natural Phenomena
    addQuestions('प्राकृतिक घटनाएँ',
        [
            { question: "Earthquake is caused by:", options: ["Movement of tectonic plates", "Volcanic eruption", "Tsunami", "Storm"], answer: "A" },
            { question: "Lightning is a:", options: ["Natural electrostatic discharge", "Chemical reaction", "Nuclear reaction", "Magnetic effect"], answer: "A" },
            { question: "Cyclone is a:", options: ["Weather phenomenon", "Geological phenomenon", "Biological phenomenon", "Nuclear phenomenon"], answer: "A" }
        ],
        [
            { question: "भूकंप किसके कारण होता है?", options: ["टेक्टोनिक प्लेटों की गति", "ज्वालामुखी विस्फोट", "सुनामी", "तूफान"], answer: "A" },
            { question: "बिजली एक:", options: ["प्राकृतिक स्थिर विद्युत विसर्जन", "रासायनिक अभिक्रिया", "नाभिकीय अभिक्रिया", "चुंबकीय प्रभाव"], answer: "A" },
            { question: "चक्रवात एक:", options: ["मौसमी घटना है", "भूवैज्ञानिक घटना है", "जैविक घटना है", "नाभिकीय घटना है"], answer: "A" }
        ]
    );

    // 10. Stars and Solar System
    addQuestions('तारे तथा सौर मण्डल',
        [
            { question: "Which is the largest planet in our solar system?", options: ["Jupiter", "Saturn", "Earth", "Neptune"], answer: "A" },
            { question: "The sun is a:", options: ["Star", "Planet", "Satellite", "Asteroid"], answer: "A" },
            { question: "Which planet is known as the red planet?", options: ["Mars", "Venus", "Jupiter", "Mercury"], answer: "A" }
        ],
        [
            { question: "हमारे सौर मंडल का सबसे बड़ा ग्रह कौन है?", options: ["बृहस्पति", "शनि", "पृथ्वी", "अरुण"], answer: "A" },
            { question: "सूर्य एक:", options: ["तारा है", "ग्रह है", "उपग्रह है", "क्षुद्रग्रह है"], answer: "A" },
            { question: "किस ग्रह को लाल ग्रह कहा जाता है?", options: ["मंगल", "शुक्र", "बृहस्पति", "बुध"], answer: "A" }
        ]
    );

    // 11. Natural Resources
    addQuestions('प्राकृतिक संसाधन',
        [
            { question: "Which is a renewable resource?", options: ["Solar energy", "Coal", "Petroleum", "Natural gas"], answer: "A" },
            { question: "Which is a non-renewable resource?", options: ["Coal", "Wind energy", "Solar energy", "Water energy"], answer: "A" },
            { question: "Conservation of resources means:", options: ["Careful use", "Excessive use", "No use", "Waste"], answer: "A" }
        ],
        [
            { question: "नवीकरणीय संसाधन कौन है?", options: ["सौर ऊर्जा", "कोयला", "पेट्रोलियम", "प्राकृतिक गैस"], answer: "A" },
            { question: "अनवीकरणीय संसाधन कौन है?", options: ["कोयला", "पवन ऊर्जा", "सौर ऊर्जा", "जल ऊर्जा"], answer: "A" },
            { question: "संसाधनों का संरक्षण क्या है?", options: ["सावधानीपूर्वक उपयोग", "अत्यधिक उपयोग", "कोई उपयोग नहीं", "बर्बादी"], answer: "A" }
        ]
    );

    // ----- PEDAGOGY TOPICS (10) -----
    // 1. Nature of Science
    addQuestions('विज्ञान की प्रकृति एवं संरचना',
        [
            { question: "Science is a:", options: ["Systematic knowledge", "Random knowledge", "Fixed knowledge", "Unchanging knowledge"], answer: "A" },
            { question: "The nature of science is:", options: ["Dynamic and evolving", "Static", "Fixed", "Unchanging"], answer: "A" },
            { question: "Science is based on:", options: ["Empirical evidence", "Belief", "Tradition", "Opinion"], answer: "A" }
        ],
        [
            { question: "विज्ञान एक:", options: ["व्यवस्थित ज्ञान है", "यादृच्छिक ज्ञान है", "निश्चित ज्ञान है", "अपरिवर्तनीय ज्ञान है"], answer: "A" },
            { question: "विज्ञान की प्रकृति:", options: ["गतिशील और विकासशील है", "स्थिर है", "निश्चित है", "अपरिवर्तनीय है"], answer: "A" },
            { question: "विज्ञान किस पर आधारित है?", options: ["अनुभवजन्य प्रमाण", "विश्वास", "परंपरा", "मत"], answer: "A" }
        ]
    );

    // 2. Aims and Objectives of Science
    addQuestions('प्राकृतिक विज्ञान लक्ष्य एवं उद्देश्य',
        [
            { question: "The aim of science education is to:", options: ["Develop scientific attitude", "Memorize facts", "Pass exams", "Get degrees"], answer: "A" },
            { question: "The objective of science teaching includes:", options: ["Understanding concepts", "Rote learning", "Exam preparation", "Only theory"], answer: "A" },
            { question: "Science education aims to develop:", options: ["Scientific temper", "Religious faith", "Superstition", "Dogmatism"], answer: "A" }
        ],
        [
            { question: "विज्ञान शिक्षा का उद्देश्य क्या है?", options: ["वैज्ञानिक दृष्टिकोण विकसित करना", "तथ्यों को याद करना", "परीक्षा उत्तीर्ण करना", "डिग्री प्राप्त करना"], answer: "A" },
            { question: "विज्ञान शिक्षण का उद्देश्य शामिल है:", options: ["अवधारणाओं को समझना", "रटना", "परीक्षा की तैयारी", "केवल सिद्धांत"], answer: "A" },
            { question: "विज्ञान शिक्षा का लक्ष्य क्या विकसित करना है?", options: ["वैज्ञानिक स्वभाव", "धार्मिक आस्था", "अंधविश्वास", "हठधर्मिता"], answer: "A" }
        ]
    );

    // 3. Importance and Understanding of Science
    addQuestions('विज्ञान का महत्त्व एवं इसकी समझ',
        [
            { question: "Science helps in:", options: ["Understanding nature", "Creating fear", "Spreading myths", "Promoting superstition"], answer: "A" },
            { question: "The importance of science lies in:", options: ["Solving daily problems", "Complicating life", "Increasing confusion", "Creating doubts"], answer: "A" },
            { question: "Science understanding is essential for:", options: ["Informed decision making", "Blind following", "Ignoring evidence", "Maintaining beliefs"], answer: "A" }
        ],
        [
            { question: "विज्ञान सहायक है:", options: ["प्रकृति को समझने में", "डर पैदा करने में", "मिथक फैलाने में", "अंधविश्वास को बढ़ावा देने में"], answer: "A" },
            { question: "विज्ञान का महत्व किसमें है?", options: ["दैनिक समस्याओं को हल करना", "जीवन को जटिल बनाना", "भ्रम बढ़ाना", "संदेह पैदा करना"], answer: "A" },
            { question: "विज्ञान की समझ किसके लिए आवश्यक है?", options: ["सूचित निर्णय लेने", "आँख बंद करके पालन", "प्रमाणों की अनदेखी", "विश्वासों को बनाए रखना"], answer: "A" }
        ]
    );

    // 4. Approaches/Integrated Approach
    addQuestions('उपागम/एकीकृत उपागम',
        [
            { question: "The integrated approach in science teaching:", options: ["Connects different subjects", "Separates subjects", "Focuses only on theory", "Ignores practicals"], answer: "A" },
            { question: "The integrated approach helps in:", options: ["Holistic learning", "Limited learning", "Memorization", "Exam focus"], answer: "A" },
            { question: "Which is a benefit of integrated approach?", options: ["Real-world connection", "Isolation of topics", "Narrow focus", "Theoretical knowledge"], answer: "A" }
        ],
        [
            { question: "विज्ञान शिक्षण में एकीकृत उपागम:", options: ["विभिन्न विषयों को जोड़ता है", "विषयों को अलग करता है", "केवल सिद्धांत पर केंद्रित है", "व्यावहारिक को अनदेखा करता है"], answer: "A" },
            { question: "एकीकृत उपागम किसमें सहायक है?", options: ["समग्र अधिगम", "सीमित अधिगम", "रटना", "परीक्षा केंद्रित"], answer: "A" },
            { question: "एकीकृत उपागम का लाभ क्या है?", options: ["वास्तविक दुनिया से जुड़ाव", "विषयों का अलगाव", "संकीर्ण ध्यान", "सैद्धांतिक ज्ञान"], answer: "A" }
        ]
    );

    // 5. Methods of Teaching Science
    addQuestions('विज्ञान शिक्षण की विधियाँ',
        [
            { question: "The scientific method involves:", options: ["Observation and experimentation", "Rote learning", "Memorization", "Only reading"], answer: "A" },
            { question: "Which method is effective in science teaching?", options: ["Laboratory method", "Lecture method only", "Dictation method", "Copying method"], answer: "A" },
            { question: "Inquiry-based learning in science emphasizes:", options: ["Student questions", "Teacher's answers", "Passive learning", "Rote memorization"], answer: "A" }
        ],
        [
            { question: "वैज्ञानिक विधि में शामिल है:", options: ["अवलोकन और प्रयोग", "रटना", "कंठस्थीकरण", "केवल पढ़ना"], answer: "A" },
            { question: "विज्ञान शिक्षण में कौन सी विधि प्रभावी है?", options: ["प्रयोगशाला विधि", "केवल व्याख्यान विधि", "श्रुतलेख विधि", "नकल विधि"], answer: "A" },
            { question: "विज्ञान में जाँच-पड़ताल-आधारित अधिगम किस पर जोर देता है?", options: ["छात्रों के प्रश्न", "शिक्षक के उत्तर", "निष्क्रिय अधिगम", "रटना"], answer: "A" }
        ]
    );

    // 6. Innovations
    addQuestions('नवाचार',
        [
            { question: "Innovation in science teaching means:", options: ["New methods and approaches", "Traditional methods", "Old approaches", "No change"], answer: "A" },
            { question: "Which is an innovative approach in science?", options: ["Project-based learning", "Only lecture", "Rote memorization", "Dictation"], answer: "A" },
            { question: "Innovation in science education helps in:", options: ["Engaging students", "Boring students", "Confusing students", "Frustrating students"], answer: "A" }
        ],
        [
            { question: "विज्ञान शिक्षण में नवाचार का अर्थ है:", options: ["नई विधियाँ और उपागम", "पारंपरिक विधियाँ", "पुराने उपागम", "कोई परिवर्तन नहीं"], answer: "A" },
            { question: "विज्ञान में नवीन उपागम कौन है?", options: ["परियोजना-आधारित अधिगम", "केवल व्याख्यान", "रटना", "श्रुतलेख"], answer: "A" },
            { question: "विज्ञान शिक्षा में नवाचार किसमें सहायक है?", options: ["छात्रों को संलग्न करना", "छात्रों को बोर करना", "छात्रों को भ्रमित करना", "छात्रों को निराश करना"], answer: "A" }
        ]
    );

    // 7. Teaching Learning Materials
    addQuestions('शिक्षण सहायक सामग्री',
        [
            { question: "Teaching learning materials in science include:", options: ["Models, charts, specimens", "Only textbooks", "Only notebooks", "Only pens"], answer: "A" },
            { question: "Which TLM is most effective for science?", options: ["Laboratory equipment", "Chalkboard only", "Textbook only", "Only oral instruction"], answer: "A" },
            { question: "The use of multimedia in science teaching:", options: ["Enhances understanding", "Confuses students", "Is useless", "Wastes time"], answer: "A" }
        ],
        [
            { question: "विज्ञान में शिक्षण सहायक सामग्री में शामिल हैं:", options: ["मॉडल, चार्ट, नमूने", "केवल पाठ्यपुस्तकें", "केवल कॉपियाँ", "केवल कलम"], answer: "A" },
            { question: "विज्ञान के लिए कौन सी शिक्षण सहायक सामग्री सबसे प्रभावी है?", options: ["प्रयोगशाला उपकरण", "केवल ब्लैकबोर्ड", "केवल पाठ्यपुस्तक", "केवल मौखिक निर्देश"], answer: "A" },
            { question: "विज्ञान शिक्षण में मल्टीमीडिया का उपयोग:", options: ["समझ को बढ़ाता है", "छात्रों को भ्रमित करता है", "बेकार है", "समय बर्बाद करता है"], answer: "A" }
        ]
    );

    // 8. Evaluation
    addQuestions('मूल्यांकन',
        [
            { question: "Evaluation in science should be:", options: ["Continuous and comprehensive", "Only final exam", "Only oral", "Only written"], answer: "A" },
            { question: "Formative assessment in science is:", options: ["During learning process", "At the end", "Only once", "For grading only"], answer: "A" },
            { question: "Summative assessment in science aims to:", options: ["Evaluate overall achievement", "Improve learning", "Diagnose difficulties", "Plan instruction"], answer: "A" }
        ],
        [
            { question: "विज्ञान में मूल्यांकन होना चाहिए:", options: ["निरंतर और व्यापक", "केवल अंतिम परीक्षा", "केवल मौखिक", "केवल लिखित"], answer: "A" },
            { question: "विज्ञान में रचनात्मक मूल्यांकन है:", options: ["अधिगम प्रक्रिया के दौरान", "अंत में", "केवल एक बार", "केवल ग्रेडिंग के लिए"], answer: "A" },
            { question: "विज्ञान में योगात्मक मूल्यांकन का उद्देश्य है:", options: ["समग्र उपलब्धि का मूल्यांकन", "सीखने में सुधार", "कठिनाइयों का निदान", "शिक्षण की योजना"], answer: "A" }
        ]
    );

    // 9. Problems in Science Teaching
    addQuestions('विज्ञान शिक्षण से सम्बन्धित समस्याएँ',
        [
            { question: "A major problem in science teaching is:", options: ["Lack of practical equipment", "Too many teachers", "Too many books", "Over-enthusiastic students"], answer: "A" },
            { question: "Which is a challenge in science teaching?", options: ["Student disinterest", "High student interest", "Good resources", "Motivated students"], answer: "A" },
            { question: "Classroom management in science is difficult due to:", options: ["Diverse learning levels", "Same level", "Perfect behavior", "Full attendance"], answer: "A" }
        ],
        [
            { question: "विज्ञान शिक्षण में प्रमुख समस्या है:", options: ["प्रायोगिक उपकरणों की कमी", "बहुत अधिक शिक्षक", "बहुत अधिक पुस्तकें", "अत्यधिक उत्साही छात्र"], answer: "A" },
            { question: "विज्ञान शिक्षण में चुनौती है:", options: ["छात्रों की अरुचि", "उच्च छात्र रुचि", "अच्छे संसाधन", "प्रेरित छात्र"], answer: "A" },
            { question: "विज्ञान में कक्षा प्रबंधन किस कारण से कठिन है?", options: ["विविध अधिगम स्तर", "समान स्तर", "परिपूर्ण व्यवहार", "पूर्ण उपस्थिति"], answer: "A" }
        ]
    );

    // 10. Remedial Teaching
    addQuestions('उपचारात्मक शिक्षण',
        [
            { question: "Remedial teaching in science aims to:", options: ["Correct errors and build concepts", "Punish students", "Skip topics", "Ignore difficulties"], answer: "A" },
            { question: "Remedial teaching should be:", options: ["Individualized and specific", "General and broad", "Rote-based", "Theory-based"], answer: "A" },
            { question: "Diagnostic test in science helps to:", options: ["Identify learning difficulties", "Assign grades", "Compare students", "Select students"], answer: "A" }
        ],
        [
            { question: "विज्ञान में उपचारात्मक शिक्षण का उद्देश्य है:", options: ["त्रुटियों को सुधारना और अवधारणाएँ बनाना", "छात्रों को दंड देना", "विषय छोड़ना", "कठिनाइयों की अनदेखी"], answer: "A" },
            { question: "उपचारात्मक शिक्षण होना चाहिए:", options: ["व्यक्तिगत और विशिष्ट", "सामान्य और व्यापक", "रट-आधारित", "सिद्धांत-आधारित"], answer: "A" },
            { question: "विज्ञान में निदानात्मक परीक्षण किसमें सहायक है?", options: ["अधिगम कठिनाइयों की पहचान", "ग्रेड देने", "छात्रों की तुलना", "छात्रों का चयन"], answer: "A" }
        ]
    );

    // Topic keys for display (21 topics)
    const topicKeys = [
        "भोजन", "द्रव्य की अवस्थाएँ", "दैनिक उपयोगी पदार्थ",
        "सजीव जगत", "मानव कार्यकी", "सूक्ष्मजीव",
        "गतिमान वस्तुएँ एवं उनके अनुप्रयोग", "चीजें कैसे काम करती हैं?",
        "प्राकृतिक घटनाएँ", "तारे तथा सौर मण्डल", "प्राकृतिक संसाधन",
        "विज्ञान की प्रकृति एवं संरचना", "प्राकृतिक विज्ञान लक्ष्य एवं उद्देश्य",
        "विज्ञान का महत्त्व एवं इसकी समझ", "उपागम/एकीकृत उपागम",
        "विज्ञान शिक्षण की विधियाँ", "नवाचार",
        "शिक्षण सहायक सामग्री", "मूल्यांकन",
        "विज्ञान शिक्षण से सम्बन्धित समस्याएँ", "उपचारात्मक शिक्षण"
    ];

    // Bilingual topic names for display (same as keys for Hindi, English mapping)
    const topicNames = {
        hi: topicKeys,
        en: [
            "Food", "States of Matter", "Daily Use Substances",
            "Living World", "Human Physiology", "Microorganisms",
            "Moving Objects & Applications", "How Things Work?",
            "Natural Phenomena", "Stars and Solar System", "Natural Resources",
            "Nature and Structure of Science", "Aims and Objectives of Science",
            "Importance and Understanding of Science", "Approaches/Integrated Approach",
            "Methods of Teaching Science", "Innovations",
            "Teaching Learning Materials", "Evaluation",
            "Problems in Science Teaching", "Remedial Teaching"
        ]
    };

    function getTopicDisplay(key, lang) {
        const idx = topicKeys.indexOf(key);
        if (idx === -1) return key;
        return topicNames[lang][idx] || key;
    }

    // UI translations
    const uiText = {
        hi: {
            mainTitle: "CTET Paper 2",
            mainSubtitle: "विज्ञान एवं शिक्षाशास्त्र (Science and Pedagogy) असाइनमेंट जनरेटर",
            startTitle: "विज्ञान एवं शिक्षाशास्त्र असाइनमेंट जनरेटर",
            startBtn: "असाइनमेंट बनाएँ",
            subjectTitle: "विषय का चयन करें",
            selectSubject: "विज्ञान एवं शिक्षाशास्त्र (Science & Pedagogy)",
            chapterTitle: "अध्याय / विषय चुनें",
            backStart: "प्रारंभ पर वापस जाएँ",
            generateAssign: "असाइनमेंट बनाएँ",
            levelTitle: "कठिनाई स्तर चुनें",
            levelDesc: "अपने असाइनमेंट के लिए स्तर का चयन करें:",
            level1: "स्तर 1",
            level1Sub: "बेसिक स्तर",
            level2: "स्तर 2",
            level2Sub: "मध्यम स्तर",
            level3: "स्तर 3",
            level3Sub: "परीक्षा स्तर",
            backChapters: "विषयों पर वापस जाएँ",
            generateFinal: "असाइनमेंट जनरेट करें",
            fullPaper: "पूर्ण पाठ्यक्रम (सभी 21 विषय)",
            noChapterAlert: "कृपया कम से कम एक अध्याय/विषय चुनें!",
            noLevelAlert: "कृपया कठिनाई स्तर चुनें!",
            fullPaperLabel: "पूर्ण पाठ्यक्रम (सभी 21 विषय)",
            instructions: "निर्देश:",
            inst1: "इस असाइनमेंट में 45 बहुविकल्पीय प्रश्न (MCQs) हैं।",
            inst2: "प्रत्येक प्रश्न के चार विकल्प हैं, केवल एक सही है।",
            inst3: "उचित विकल्प का चयन करें।",
            inst4: "समय: 60 मिनट",
            mcqHeading: "बहुविकल्पीय प्रश्न (MCQs)",
            answerKey: "उत्तर कुंजी (Answer Key)",
            qNo: "प्रश्न सं.",
            ans: "उत्तर",
            print: "प्रिंट करें",
            download: "PDF डाउनलोड करें",
            newAssign: "नया असाइनमेंट",
            subjectLabel: "विज्ञान एवं शिक्षाशास्त्र",
            langLabel: "हिंदी",
            noQuestions: "प्रश्न उपलब्ध नहीं हैं। कृपया अन्य अध्याय चुनें।"
        },
        en: {
            mainTitle: "CTET Paper 2",
            mainSubtitle: "Science and Pedagogy Assignment Generator",
            startTitle: "Science and Pedagogy Assignment Generator",
            startBtn: "Create Assignment",
            subjectTitle: "Select Subject",
            selectSubject: "Science & Pedagogy",
            chapterTitle: "Select Chapters / Topics",
            backStart: "Back to Start",
            generateAssign: "Generate Assignment",
            levelTitle: "Select Difficulty Level",
            levelDesc: "Choose the level for your assignment:",
            level1: "Level 1",
            level1Sub: "Basic Level",
            level2: "Level 2",
            level2Sub: "Medium Level",
            level3: "Level 3",
            level3Sub: "Exam Level",
            backChapters: "Back to Topics",
            generateFinal: "Generate Assignment",
            fullPaper: "Full Syllabus (All 21 Topics)",
            noChapterAlert: "Please select at least one chapter/topic!",
            noLevelAlert: "Please select a difficulty level!",
            fullPaperLabel: "Full Syllabus (All 21 Topics)",
            instructions: "Instructions:",
            inst1: "This assignment has 45 multiple-choice questions (MCQs).",
            inst2: "Each question has four options, only one is correct.",
            inst3: "Select the appropriate option.",
            inst4: "Time: 60 minutes",
            mcqHeading: "Multiple Choice Questions (MCQs)",
            answerKey: "Answer Key",
            qNo: "Q. No.",
            ans: "Answer",
            print: "Print",
            download: "Download PDF",
            newAssign: "New Assignment",
            subjectLabel: "Science & Pedagogy",
            langLabel: "English",
            noQuestions: "Questions not available. Please select other chapters."
        }
    };

    // DOM refs
    const langToggleBtn = document.getElementById('langToggleBtn');
    const langLabel = document.getElementById('langLabel');
    let currentLang = 'hi';

    function applyUILanguage(lang) {
        const t = uiText[lang];
        document.getElementById('mainTitle').textContent = t.mainTitle;
        document.getElementById('mainSubtitle').textContent = t.mainSubtitle;
        document.getElementById('startTitle').textContent = t.startTitle;
        document.getElementById('startGeneratingBtn').textContent = t.startBtn;
        document.getElementById('subjectTitle').textContent = t.subjectTitle;
        document.getElementById('selectScienceBtn').textContent = t.selectSubject;
        document.getElementById('chapterTitle').textContent = t.chapterTitle;
        document.getElementById('backToStartBtn').textContent = t.backStart;
        document.getElementById('generateAssignmentBtn').textContent = t.generateAssign;
        document.getElementById('levelTitle').textContent = t.levelTitle;
        document.getElementById('levelDesc').textContent = t.levelDesc;
        document.getElementById('level1Btn').innerHTML = `${t.level1}<br><small>${t.level1Sub}</small>`;
        document.getElementById('level2Btn').innerHTML = `${t.level2}<br><small>${t.level2Sub}</small>`;
        document.getElementById('level3Btn').innerHTML = `${t.level3}<br><small>${t.level3Sub}</small>`;
        document.getElementById('backToChaptersBtn').textContent = t.backChapters;
        document.getElementById('generateFinalBtn').textContent = t.generateFinal;
        langLabel.textContent = t.langLabel;
        populateChapters();
        if (!generatedPaperContainer.classList.contains('hidden')) {
            if (selectedChapters && selectedLevel) {
                generatePaper(selectedChapters, selectedLevel, currentLang);
            }
        }
    }

    langToggleBtn.addEventListener('click', function() {
        currentLang = (currentLang === 'hi') ? 'en' : 'hi';
        applyUILanguage(currentLang);
    });

    // ----- Core logic -----
    let selectedChapters = [];
    let selectedLevel = null;
    const startContainer = document.getElementById('startContainer');
    const startScreen = document.getElementById('startScreen');
    const subjectSelection = document.getElementById('subjectSelection');
    const chapterSelection = document.getElementById('chapterSelection');
    const levelSelection = document.getElementById('levelSelection');
    const generatedPaperContainer = document.getElementById('generatedPaperContainer');

    function populateChapters() {
        const container = document.getElementById('chapterCheckboxContainer');
        const t = uiText[currentLang];
        const fullPaperLabel = (currentLang === 'hi') ? "पूर्ण पाठ्यक्रम (सभी 21 विषय)" : "Full Syllabus (All 21 Topics)";
        container.innerHTML = `<div class="checkbox-item"><input type="checkbox" id="fullPaper" value="full"><label for="fullPaper">${fullPaperLabel}</label></div>`;
        topicKeys.forEach((key, idx) => {
            const displayName = getTopicDisplay(key, currentLang);
            container.innerHTML += `<div class="checkbox-item"><input type="checkbox" id="topic_${idx}" name="chapter" value="${key}"><label for="topic_${idx}">${idx+1}. ${displayName}</label></div>`;
        });
        const fullPaperCheckbox = document.getElementById('fullPaper');
        if(fullPaperCheckbox) {
            fullPaperCheckbox.addEventListener('change', function() {
                const allChapterCheckboxes = document.querySelectorAll('input[name="chapter"]');
                allChapterCheckboxes.forEach(cb => cb.disabled = this.checked);
            });
        }
    }

    function getRandomQuestions(chapters, level, count, lang) {
        let allQuestions = [];
        chapters.forEach(ch => {
            if(questionBank[ch] && questionBank[ch][lang] && questionBank[ch][lang][`level${level}`]) {
                allQuestions = allQuestions.concat(questionBank[ch][lang][`level${level}`]);
            }
        });
        if(allQuestions.length === 0) {
            const t = uiText[lang];
            return [{ question: t.noQuestions, options: ["A", "B", "C", "D"], answer: "A" }];
        }
        allQuestions = allQuestions.sort(() => Math.random() - 0.5);
        return allQuestions.slice(0, Math.min(count, allQuestions.length));
    }

    function generatePaper(chapters, level, lang) {
        const t = uiText[lang];
        const mcqs = getRandomQuestions(chapters, level, 45, lang);
        let questionNumber = 1;
        let chapterDisplay = '';
        if (chapters.length === topicKeys.length) {
            chapterDisplay = t.fullPaperLabel;
        } else {
            const displayNames = chapters.slice(0,3).map(k => getTopicDisplay(k, lang));
            chapterDisplay = displayNames.join(", ") + (chapters.length > 3 ? "..." : "");
        }
        let paperContent = `
            <div class="header">
                <h2>CTET Paper 2 - ${t.subjectLabel}</h2>
                <h3>${chapterDisplay}</h3>
                <p>${level === 1 ? t.level1 : level === 2 ? t.level2 : t.level3} - ${level === 1 ? t.level1Sub : level === 2 ? t.level2Sub : t.level3Sub}</p>
            </div>
            <div class="content-area">
                <div class="instructions">
                    <p><strong>${t.instructions}</strong></p>
                    <ol>
                        <li>${t.inst1}</li>
                        <li>${t.inst2}</li>
                        <li>${t.inst3}</li>
                        <li>${t.inst4}</li>
                    </ol>
                </div>
                <div class="question-section">
                    <div class="section-heading">${t.mcqHeading}</div>`;

        mcqs.forEach(mcq => {
            paperContent += `
                <div class="question">
                    <div class="question-text">${questionNumber}. ${mcq.question}</div>
                    <div class="option">A. ${mcq.options[0]}</div>
                    <div class="option">B. ${mcq.options[1]}</div>
                    <div class="option">C. ${mcq.options[2]}</div>
                    <div class="option">D. ${mcq.options[3]}</div>
                </div>`;
            questionNumber++;
        });

        paperContent += `
                </div>
                <div class="answer-sheet">
                    <h3 class="section-title">${t.answerKey}</h3>
                    <table class="answer-table">
                        <thead>
                            <tr>
                                <th>${t.qNo}</th><th>${t.ans}</th>
                                <th>${t.qNo}</th><th>${t.ans}</th>
                                <th>${t.qNo}</th><th>${t.ans}</th>
                            </tr>
                        </thead>
                        <tbody>`;

        for(let i=0; i<mcqs.length; i+=3) {
            paperContent += `<tr>`;
            for(let j=0; j<3; j++) {
                if(i+j < mcqs.length) {
                    paperContent += `<td>${i+j+1}</td><td>${mcqs[i+j].answer}</td>`;
                } else {
                    paperContent += `<td></td><td></td>`;
                }
            }
            paperContent += `</tr>`;
        }

        paperContent += `
                        </tbody>
                    </table>
                </div>
                <div class="action-buttons">
                    <button class="btn btn-primary" id="printBtn"><i class="fas fa-print"></i> ${t.print}</button>
                    <button class="btn btn-success" id="downloadBtn"><i class="fas fa-download"></i> ${t.download}</button>
                    <button class="btn btn-danger" id="newAssignmentBtn"><i class="fas fa-plus"></i> ${t.newAssign}</button>
                </div>
            </div>`;

        generatedPaperContainer.innerHTML = paperContent;
        generatedPaperContainer.classList.remove('hidden');
        startContainer.classList.add('hidden');

        document.getElementById('printBtn').addEventListener('click', function() { window.print(); });
        document.getElementById('downloadBtn').addEventListener('click', downloadPDF);
        document.getElementById('newAssignmentBtn').addEventListener('click', function() {
            generatedPaperContainer.classList.add('hidden');
            startContainer.classList.remove('hidden');
            startScreen.classList.remove('hidden');
            subjectSelection.classList.add('hidden');
            chapterSelection.classList.add('hidden');
            levelSelection.classList.add('hidden');
            selectedLevel = null;
            level1Btn.classList.remove('selected');
            level2Btn.classList.remove('selected');
            level3Btn.classList.remove('selected');
        });
    }

    // Event Listeners
    document.getElementById('startGeneratingBtn').addEventListener('click', function() {
        startScreen.classList.add('hidden');
        subjectSelection.classList.remove('hidden');
    });

    document.getElementById('selectScienceBtn').addEventListener('click', function() {
        subjectSelection.classList.add('hidden');
        populateChapters();
        chapterSelection.classList.remove('hidden');
    });

    document.getElementById('backToStartBtn').addEventListener('click', function() {
        generatedPaperContainer.classList.add('hidden');
        startContainer.classList.remove('hidden');
        chapterSelection.classList.add('hidden');
        levelSelection.classList.add('hidden');
        startScreen.classList.remove('hidden');
        subjectSelection.classList.add('hidden');
    });

    document.getElementById('generateAssignmentBtn').addEventListener('click', function() {
        const fullPaper = document.getElementById('fullPaper');
        if(fullPaper && fullPaper.checked) {
            selectedChapters = [...topicKeys];
        } else {
            selectedChapters = Array.from(document.querySelectorAll('input[name="chapter"]:checked')).map(cb => cb.value);
        }
        if(selectedChapters.length === 0) {
            const t = uiText[currentLang];
            alert(t.noChapterAlert);
            return;
        }
        chapterSelection.classList.add('hidden');
        levelSelection.classList.remove('hidden');
    });

    document.getElementById('backToChaptersBtn').addEventListener('click', function() {
        levelSelection.classList.add('hidden');
        chapterSelection.classList.remove('hidden');
    });

    function selectLevel(level) {
        level1Btn.classList.remove('selected');
        level2Btn.classList.remove('selected');
        level3Btn.classList.remove('selected');
        document.getElementById(`level${level}Btn`).classList.add('selected');
        selectedLevel = level;
    }

    document.getElementById('level1Btn').addEventListener('click', function() { selectLevel(1); });
    document.getElementById('level2Btn').addEventListener('click', function() { selectLevel(2); });
    document.getElementById('level3Btn').addEventListener('click', function() { selectLevel(3); });

    document.getElementById('generateFinalBtn').addEventListener('click', function() {
        if(!selectedLevel) {
            const t = uiText[currentLang];
            alert(t.noLevelAlert);
            return;
        }
        startContainer.classList.add('hidden');
        levelSelection.classList.add('hidden');
        generatePaper(selectedChapters, selectedLevel, currentLang);
    });

    // PDF Download
    async function downloadPDF() {
        const element = document.getElementById('generatedPaperContainer');
        const tempDiv = document.createElement('div');
        tempDiv.style.position = 'absolute';
        tempDiv.style.left = '-9999px';
        tempDiv.style.width = '794px';
        tempDiv.style.backgroundColor = 'white';
        tempDiv.style.padding = '20px';
        tempDiv.innerHTML = element.innerHTML;
        document.body.appendChild(tempDiv);
        
        try {
            const pdf = new jsPDF('p', 'mm', 'a4');
            const pageWidth = pdf.internal.pageSize.getWidth() - 25.4;
            const pageHeight = pdf.internal.pageSize.getHeight() - 25.4;
            let position = 12.7;
            let remainingHeight = tempDiv.scrollHeight;
            let pageNum = 1;
            
            while(remainingHeight > 0) {
                const canvas = await html2canvas(tempDiv, { 
                    scale: 2,
                    windowHeight: pageHeight * 3.78,
                    windowWidth: pageWidth * 3.78,
                    y: position * 3.78,
                    height: pageHeight * 3.78,
                    useCORS: true,
                    backgroundColor: '#ffffff',
                    logging: false 
                });
                const imgData = canvas.toDataURL('image/jpeg', 0.95);
                if(pageNum > 1) pdf.addPage('a4', 'portrait');
                pdf.addImage(imgData, 'JPEG', 12.7, 12.7, pageWidth, (canvas.height * pageWidth) / canvas.width);
                position += pageHeight;
                remainingHeight -= pageHeight * 3.78;
                pageNum++;
            }
            pdf.save('CTET_Science_Pedagogy_Assignment.pdf');
        } catch(err) { 
            console.error(err); 
            alert('PDF generation error. Please try again.'); 
        } finally { 
            if(tempDiv && tempDiv.parentNode) document.body.removeChild(tempDiv); 
        }
    }

    // Home icon
    document.getElementById('homeIconBtn').addEventListener('click', function(e) {
        e.preventDefault();
        generatedPaperContainer.classList.add('hidden');
        startContainer.classList.remove('hidden');
        startScreen.classList.remove('hidden');
        subjectSelection.classList.add('hidden');
        chapterSelection.classList.add('hidden');
        levelSelection.classList.add('hidden');
        selectedLevel = null;
        level1Btn.classList.remove('selected');
        level2Btn.classList.remove('selected');
        level3Btn.classList.remove('selected');
    });

    // Initial load
    applyUILanguage('hi');
</script>
</body>
</html>