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: Medicine
Infectivity of chicken pox is seen- 
Select and explain. 
A. Till last scab falls off, B. 3 days after the appearance of rash, C. 6 days after the appearance of rash, D. As long as the fever lasts
C: 6 days after the appearance of rash
Answer: C: 6 days after the appearance of rash 
Explanation: None