This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Tumors, Subject name: Orthopaedics
[{'content': "Which of the following condition is considered as a premalignant condition for secondary osteosarcoma? \nSelect and explain. \nA. Paget's disease, B. Enchondromatosis, C. Diaphyseal aclasis, D. All of the above", 'role': 'user'}, {'content': "Answer: D \nExplanation: Pre-malignant bone lesions of secondary osteosarcoma : Paget's disease Diaphyseal aclasis Enchondromatosis Post-radiation Fibrous dysplasia Reference: Maheshwari; Essential Ohopaedics 9th ed; Page no: 242", 'role': 'assistant'}]