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': 'Maxillary primary cuspid enamel completion takes place at: \nSelect and explain. \nA. 6 months in utero, B. 6 months after birth, C. 9 months in utero, D. 9 months after birth', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]