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': 'Dacron vascular, graft is \nSelect and explain. \nA. Nontextile synthetic, B. Textile synthetic, C. Nontextile biologic, D. Textile biologic', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Textile synthetic graft → Dacron\nNontextile synthetic graft → PTFE (polytetra fluoro ethylene)', 'role': 'assistant'}]