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: Surgery
[{'content': 'The expression of the following oncogene is associated with a high incidence of Medullary carcinomas of thyroid \nSelect and explain. \nA. p53, B. Her 2 neu, C. Ret proto-oncogene, D. Rb gene', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]