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': 'Most common primary bone tumour of hand is: \nSelect and explain. \nA. Osteoma, B. Osteochondroma, C. Enchondroma, D. None of the above', 'role': 'user'}, {'content': "Answer: C \nExplanation: Enchondromas arise from cailage and are the most common primary bone tumors of the hand. These lesions account for >90% of bone tumors seen in the hand. Ref: Schwaz's principle of surgery 9th edition, chapter 44.", 'role': 'assistant'}]