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': 'Tumors most amenable (cured with) to chemotherapy  a) Chorio Ca  b) Embryonal rhabdomyosarcoma  c) Hepatocellular Ca  d) Thyroid Ca \nSelect and explain. \nA. ab, B. abc, C. abd, D. ac', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]