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': "Head shape in Down's syndrome is typically \nSelect and explain. \nA. Mesocephalic, B. Dolicocephalic, C. Brachycephalic, D. Acephalic", 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]