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
International disease surveillance is for ? 
Select and explain. 
A. Hepatitis, B. Polio, C. TB, D. Leprosy
B: Polio
Answer: B: Polio 
Explanation: Ans. is 'b' i.e., Polio