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 of the following are diaphyseal tumors except? \nSelect and explain. \nA. Ewings sarcoma, B. Histiocytosis, C. Fibrosarcoma, D. Aneurysmal bone cyst', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans. is d i.e., Aneurysmal bone cyst', 'role': 'assistant'}]