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: Radiology
[{'content': 'Dense calcification is seen in \nSelect and explain. \nA. Chondroblatoma, B. Chondrosarcoma, C. Osteosarcoma, D. Fibrosarcoma', 'role': 'user'}, {'content': 'Answer: B \nExplanation: B i.e. Chondrosarcoma - Most common bone tumor = Osteochondroma Bone tumor with Dense calcification = Chondro Sarcoma Bone tumor with Calcified secondaries = Osteosarcoma', 'role': 'assistant'}]