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': 'In the demographic cycle, the contraction of demographic gap starts in \nSelect and explain. \nA. Early part of II stage, B. Late part of II stage, C. Early part of III stage, D. Late part of III stage', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]