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': 'In traumatic injury to common femoral vein & external femoral artery, which among the following should be done - \nSelect and explain. \nA. Ligation of both artery & vein, B. Repair of artery & vein, C. Below knee amputation, D. Repair of artery and contralateral sympathectomy', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]