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': '1st evidence of calcification of maxillary 2nd molar is seen in \nSelect and explain. \nA. 2 year, B. 2 ½ to 3 year, C. 7-8 year, D. At birth', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]