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: Social & Preventive Medicine
Which is not true about Yellow fever 
Select and explain. 
A. Exotic, B. Incubation period 2-6 days, C. Live Attenuated 17 D strain vaccine, D. Validity of vaccine 6 years
D: Validity of vaccine 6 years
Answer: D: Validity of vaccine 6 years 
Explanation: None