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': 'All except one are true regarding modified perthes test \nSelect and explain. \nA. Tourniquet applied below saphenofemoral junction, B. Only subjective test, C. There should be no perforator incompetence to do this test, D. Shrinkage of varicose veins on testing indicates normal deep veins', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Modified perthes test is both subjective and objective test,', 'role': 'assistant'}]