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: Skin
[{'content': 'Normal turnover time of epidermis (skin doubling time) is \nSelect and explain. \nA. 2 weeks, B. 4 weeks, C. 6 weeks, D. 8 weeks', 'role': 'user'}, {'content': 'Answer: B \nExplanation: B i.e. 4 weeks', 'role': 'assistant'}]