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: Pediatrics
Measles is infectious during – 
Select and explain. 
A. After 4 days of rash, B. 4 days before and 5 days after rash, C. Throughout disease, D. Only in incubation period
B: 4 days before and 5 days after rash
Answer: B: 4 days before and 5 days after rash 
Explanation: Period of communicability for measles is 4 days before and 5 days after appearance of rash.