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: Surgery
[{'content': 'A fracture mandible should be immobilized for an\naverage of \nSelect and explain. \nA. 3 weeks, B. 6 weeks, C. 9 weeks, D. 12 weeks', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]