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': "All are the predisposing factors of osteogenic sarcoma except - \nSelect and explain. \nA. Paget's disease of bone, B. Radiation, C. Viral infection, D. Bone infarction", 'role': 'user'}, {'content': 'Answer: C \nExplanation: Causes of secondary osteosarcoma :\xa0\n\nPaget disease\xa0\nFibrous dysplasia\nMultiple osteochondroma\nChronic osteomyelitis\nRadiation\xa0\xa0\nEnchondromatosis\xa0\xa0\nBone infarction', 'role': 'assistant'}]