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: Surgery
A patient presents with pain in the thigh, relieved by aspirin. X-ray shows a radiolucent mass surrounded by sclerosis. Diagnosis is ? 
Select and explain. 
A. Osteoma, B. Osteoid osteoma, C. Osteoblastoma, D. Osteoclastoma
B: Osteoid osteoma
Answer: B: Osteoid osteoma 
Explanation: Ans. is 'b' i.e., Osteoid osteoma Radiolucent lesion with surrounded sclerosis and pain relief by a salicylate (aspirin) are characteristics of osteoid osteoma.