This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Non communicable diseases, Subject name: Social & Preventive Medicine
[{'content': 'Crude bih rate denominator is - \nSelect and explain. \nA. Total no of live bihs in that year, B. 1000 live bihs, C. Total number of bihs, D. Mid year population', 'role': 'user'}, {'content': 'Answer: D \nExplanation: <p> Crude bih rate= Number of live bihs in a year per 1000 mid-year population. Reference:Park&;s textbook of preventive and social medicine,K.Park,23rd edition,page no:488. <\\p>', 'role': 'assistant'}]