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: Medicine
[{'content': "Radio resistant tumours are - a) Melanoma  b) HD  c) Seminoma  d) Ewing's sarcoma  e) Chondro sarcoma \nSelect and explain. \nA. ae, B. bc, C. ad, D. ab", 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]