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': 'A patient presents with pain in the thigh, relieved by aspirin. X-ray shows a radiolucent mass surrounded by sclerosis. Diagnosis is - \nSelect and explain. \nA. Osteoma, B. Osteoid osteoma, C. Osteoblastoma, D. Osteoclastoma', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Radioluscent lesion with surrounded sclerosis and pain relived by a salicylate are characteristic of Osteoid osteoma Refer Maheshwari 9TH ED p 235', 'role': 'assistant'}]