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': 'The most important perforator of the Lower limb is between - \nSelect and explain. \nA. Long saphenous and posterior tibial vein, B. Short saphenous and posterior tibial vein, C. Short saphenous and popliteal vein, D. Long saphenous and femoral vein', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]