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': "An 8-year-old boy presents with a gradually progressing swelling and pain since 6 months over the upper tibia. On x-ray, there is a lytic lesion with sclerotic margins in the upper tibial metaphysis. The diagnosis is - \nSelect and explain. \nA. Osteogenic sarcoma, B. Osteoclastoma, C. Brodie's abscess, D. Ewing's sarcoma", 'role': 'user'}, {'content': "Answer: C \nExplanation: Lytic lesion with sclerotic margin in upper end of tibia in an 8-year-old by suggests the diagnosis of Brodie's abscess (among the given options).\nLytic lesions with sclerotic margins is seen in : -\n\ni)\xa0Simple bone cyst \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0\nii) Brodie's abscess\xa0\xa0\niii) Osteoblastoma\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\niv) Chondroblastoma", 'role': 'assistant'}]