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': 'The index age group for deciduous teeth in year is: \nSelect and explain. \nA. 12, B. 5, C. 35 - 44, D. 65 - 74', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]