[{"id": 1, "type": "multiple_choice", "options": ["Nucleus", "Cell membrane", "Mitochondria", "Ribosome"], "question": "What organelle is known as the \"powerhouse of the cell\"?", "correct_answer": "Mitochondria"}, {"id": 2, "type": "written_response", "question": "Explain the scientific concept covered in \"Human Impact on Environment Practice\" and provide a real-world example.", "correct_answer": null}, {"id": 3, "type": "multiple_choice", "options": ["Large, small, tiny", "Igneous, sedimentary, metamorphic", "Hard, soft, medium", "Red, gray, black"], "question": "What are the three types of rocks?", "correct_answer": "Igneous, sedimentary, metamorphic"}, {"id": 4, "type": "multiple_choice", "options": ["Ribosome", "Mitochondria", "Nucleus", "Cell membrane"], "question": "What organelle is known as the \"powerhouse of the cell\"?", "correct_answer": "Mitochondria"}, {"id": 5, "type": "multiple_choice", "options": ["H₂O", "O₂", "NaCl", "CO₂"], "question": "What is the chemical symbol for water?", "correct_answer": "H₂O"}]