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: Microbiology
Most common viral disease affecting parotid glands- 
Select and explain. 
A. Mumps, B. Measles, C. Rubella, D. Varicella
A: Mumps
Answer: A: Mumps 
Explanation: None