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
Shoest incubation period is seen in? 
Select and explain. 
A. Influenza, B. Hepatitis B, C. Hepatitis A, D. Rubella
A: Influenza
Answer: A: Influenza 
Explanation: Ans. is 'a' i.e., Influenza o Mumps 16 - 18 days o Influenza 2 - 3 days o Hepatitis A > 15 - 90 days o Hepatitis B 6 wk to 6 months