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
[{'content': 'Infants constitute what % of population? \nSelect and explain. \nA. 2, B. 3, C. 4, D. 5', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is 'b' i.e., 3", 'role': 'assistant'}]