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
A 8-year old boy presented with swelling on both
sides of the face, below the ears of 4 days duration.
It first started on the left side and then 3 days 
later on the right side

Immunization to this disease can be achieved by the following vaccination 
Select and explain. 
A. MMR, B. BCG, C. Hepatitis B, D. Polio
A: MMR
Answer: A: MMR 
Explanation: None