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': 'MC malignant bone tumour is: September 2003 \nSelect and explain. \nA. Osteosarcoma, B. Osteoclastoma, C. Secondaries, D. Multiple myeloma', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans. C i.e. Secondaries', 'role': 'assistant'}]