This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Epidemiology, Subject name: Social & Preventive Medicine
Incubatory carrier seen in - 
Select and explain. 
A. Cholera, B. Bubonic plague, C. Mumps, D. Measles
C: Mumps
Answer: C: Mumps 
Explanation: Period of communicability of mumps : Usually 4-6 days before the onset of symptoms and a week or more thereafter. The period of maximum infectivity is just before and at the onset of parotitis. Ref: 25th edition, Park's Textbook of Preventive and Social Medicine, Page no. 165