This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General physiology, Subject name: Physiology
[{'content': 'Myelin contains protein to lipid ratio as \nSelect and explain. \nA. 1:01, B. 2:01, C. 3:01, D. 1:04', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]