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: Medicine
[{'content': 'True about measles is all except: \nSelect and explain. \nA. Measles shows a Cyclical trend, B. Koplik spots seen on buccal mucosa opposite upper 2nd molar, C. Incubation period is 10-14 days, D. SAR is 80%', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Koplik spots seen opposite lower 2nd molar.', 'role': 'assistant'}]