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 Upper 1st premolar is seen in \nSelect and explain. \nA. at birth, B. 1-1 ½ year, C. 4 year, D. 2 years', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]