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: ENT
[{'content': 'Maxilla achieves maximum size at- \nSelect and explain. \nA. At birth, B. At primary dentition, C. At secondary dentition, D. At puberty', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]