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: Social & Preventive Medicine
Measles vaccine is not given before: 
Select and explain. 
A. 9 months, B. 12 months, C. 15 months, D. 18 months
A: 9 months
Answer: A: 9 months 
Explanation: 9 months