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 Mandibular deciduous Lateral incisor occurs \nSelect and explain. \nA. 14 wk IU, B. 16 wk IU, C. 17 wk IU, D. 15 wk IU', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]