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': 'First step of treatment of a person with FAP family history is \nSelect and explain. \nA. colonoscopy, B. Total colectomy, C. Gene testing, D. Frozen section', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Gene testing is performed first. If positive screening begins from 10 years of age.', 'role': 'assistant'}]