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': 'Width of division B bone is about \nSelect and explain. \nA. <2.5 mm, B. 2.5-5 mm, C. >5 mm, D. None of the above', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]