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 features of Thromboangitis obliterans \nSelect and explain. \nA. Initimal hyperplasia, B. Panarteritis, C. Vasospasmitis, D. Arterial thickening', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Arterial Lumen is blocked but not thickened in TAO.', 'role': 'assistant'}]