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: Medicine
Hepatitis B occurs after an incubation period of: 
Select and explain. 
A. 1 week, B. 3 weeks, C. 3 months, D. 6 months
C: 3 months
Answer: C: 3 months 
Explanation: None