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 a outbreak of cholera in village of 2,000 population, 20 cases have occurred and 5 died. Case fatality rate is - \nSelect and explain. \nA. 1%, B. 0.25%, C. 5%, D. 25%', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., 25%", 'role': 'assistant'}]