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: Dental
[{'content': 'Rapid progressive juvenile periodontitis is seen usually at which age? \nSelect and explain. \nA. 6-10 years, B. 10-20 years, C. 30-40 years, D. At any age', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]