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': 'Case fatality rate is a method of measuring ? \nSelect and explain. \nA. Infectivity, B. Pathogenecity, C. Virulence, D. Average duration of disease', 'role': 'user'}, {'content': "Answer: C \nExplanation: Ans. is 'c' i.e., Virulence CFR is closely related to virulence of agent.", 'role': 'assistant'}]