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': 'On average, approximately what is the dimension of the permanent maxillary canine at the widest mesiodistal diameter of the crown? \nSelect and explain. \nA. 5.5 mm., B. 6.5 mm., C. 7.5 mm., D. 8.5 mm.', 'role': 'user'}, {'content': 'Answer: C \nExplanation: The dimension of the permanent maxillary canine at the widest MD diameter is 7.5 mm (7.5 mm (Ash and Nelson, 2003); 7.6 mm ).', 'role': 'assistant'}]