This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General anatomy, Subject name: Anatomy
[{'content': 'Decreased protein lipid ratio seen in: \nSelect and explain. \nA. Inner mitochondrial membrane, B. Outer mitochondrial membrane, C. Sarcoplasmic reticulum, D. Myelin sheath membrane', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Nerve cell membrane with myelin sheath are rich in lipid ,about 80%', 'role': 'assistant'}]