This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General anatomy, Subject name: Anatomy
[{'content': 'A patient was on DVT prophylaxis. All of the following has perforations which connect Superficial veins to the deep veins except \nSelect and explain. \nA. Ankle, B. Below inguinal ligament, C. Mid calf, D. Lower thigh', 'role': 'user'}, {'content': "Answer: B \nExplanation: With this option, this could be the only possible answer as sho saphenous vein is a tributary of polite all vein which is formed by union of anterior and posterior tibial veins. Ref: Gray's 38e/p38-1597", 'role': 'assistant'}]