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 of the following occurs in epiphysis-a) Osteoclastomab) Chondroblastomac) Osteochondromad) Ewing's sarcomae) Chondrosarcoma \nSelect and explain. \nA. ac, B. ab, C. ad, D. bc", 'role': 'user'}, {'content': 'Answer: B \nExplanation: Epiphvseal tumors : - Chondroblastoma, Giant cell tumor (osteoclastoma), Clear cell chondrosaroma.', 'role': 'assistant'}]