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
One TB infected person can infect how many people in 1 year? 
Select and explain. 
A. 10, B. 30, C. 20, D. 5
A: 10
Answer: A: 10 
Explanation: None