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
Normal turnover time of epidermis (skin doubling time) is 
Select and explain. 
A. 2 weeks, B. 4 weeks, C. 6 weeks, D. 8 weeks
B: 4 weeks
Answer: B: 4 weeks 
Explanation: B i.e. 4 weeks