This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Measurement of Mortality and Morbidity, Subject name: Social & Preventive Medicine
[{'content': 'Number of live birth per 1000 women in reproductive age group is? \nSelect and explain. \nA. TFR, B. GFR, C. NRR, D. GRR', 'role': 'user'}, {'content': 'Answer: B \nExplanation: ANSWER: (B) GFRREF: Park 20th ed page 419, style="font-size: 1.04761904761905em; font-family: Times New Roman, Times, serif; margin: 0 0 0 8px; text-indent: 0; text-align: left">See previous question', 'role': 'assistant'}]