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 syphilis - \nSelect and explain. \nA. 1 hour - 5 hour, B. 24 hour - 48 hour, C. 1 days - 10 days, D. 10 days - 90 days', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]