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: Orthopaedics
[{'content': "Which one of the following bone tumors typically affects the epiphysis of a long bone - \nSelect and explain. \nA. Osteosarcoma, B. Ewing's sarcoma, C. Chondroblastoma, D. Chondromyxoid fibroma", 'role': 'user'}, {'content': 'Answer: C \nExplanation: It occurs mostly in the epiphysis of long bones.', 'role': 'assistant'}]