This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Physiology
[{'content': 'In cell membrane, on the basis of mass, proteins and lipids are present at a ratio of \nSelect and explain. \nA. 1:02, B. 1:01, C. 2:01, D. 4:01', 'role': 'user'}, {'content': 'Answer: B \nExplanation: According to \'Principles of Medical Physiology\', "The cell membrane contains proteins and lipids in 50:50 ratios. This refers to the ratio of their masses and not numbers".', 'role': 'assistant'}]