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 epidemic, 1st step is- \nSelect and explain. \nA. Verification of diagnosis, B. Isolation, C. Immunization, D. Notification', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Verification of diagnosis", 'role': 'assistant'}]