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
All are true about Yellow Fever except 
Select and explain. 
A. Incubation period is 3-6 days, B. Validity of Int’l certificate of Vaccination lasts up to 10 years, C. Urban form is controlled by 17 D vaccine, D. Aedes aegypti index should not be more than 10% to ensure freedom from yellow Fever
D: Aedes aegypti index should not be more than 10% to ensure freedom from yellow Fever
Answer: D: Aedes aegypti index should not be more than 10% to ensure freedom from yellow Fever 
Explanation: • Incubation Period: 3 – 6 days
• Yellow Fever Vaccine:
Live attenuated, lyophilized (Freeze dried) vaccine
Strain: 17D strain (Chick Embryo grown)
Reconstitution with Diluent: Cold physiological saline
Immunity lasts: From 7 days of Vaccination till 35 years
WHO recommended validity of Vaccination Certificate for International travel: from 10 days to 10 years
YF vaccine is the only Live vaccine that can be administered in Pregnancy (if there is risk of exposure)