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: Microbiology
[{'content': 'Incubation period of Diptheria is - \nSelect and explain. \nA. 2 - 6 days, B. 2 - 6 hrs, C. 2 - 6 weeks, D. 2 - 6 months', 'role': 'user'}, {'content': "Answer: A \nExplanation: . Ans. is `a' i.e., 2 - 6 days - The incubation period of diphtheria is commonly 3-4 days.", 'role': 'assistant'}]