This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Skeletal system, Subject name: Radiology
[{'content': "Radioresistant tumor is \nSelect and explain. \nA. Ewing's sarcoma, B. Osteosarcoma, C. Retinoblastoma, D. Neuroblastoma", 'role': 'user'}, {'content': 'Answer: B \nExplanation: List of highly radioresistant tumors : Osteosarcoma Melanoma Pancreatic cancer Hepatocellular carcinoma', 'role': 'assistant'}]