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: Orthopaedics
[{'content': 'Most common cause of amputation is \nSelect and explain. \nA. Trauma, B. Peripheral vascular disease, C. Frost bite, D. Burns', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]