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': 'Net reproductive rate=1 can be achieved if couple protection rate is more than: \nSelect and explain. \nA. 40%, B. 50%, C. 60%, D. 70%', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Demographic goal of Net reproductive rate=1 can be achieved if couple protection rate is more than 60%. Ref: Park, 22nd edition pg: 455', 'role': 'assistant'}]