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': 'For calculation of incidence denominator is taken as? \nSelect and explain. \nA. Mid year population, B. Population at risk, C. Total number of cases, D. Total number of deaths', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is 'b' i.e., Population at risk o Denominator for calculating incidence is population at risk", 'role': 'assistant'}]