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': 'The number of line angles in a permanent maxillary central incisor is \nSelect and explain. \nA. Two, B. Four, C. Six, D. Eight', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]