This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Urology, Subject name: Surgery
[{'content': 'Which is a nonabsorbable suture \nSelect and explain. \nA. Vicryl, B. Polypropylene, C. Catgut, D. PDS', 'role': 'user'}, {'content': "Answer: B \nExplanation: Absorbable suture materials are: plain catgut, chromic catgut, vicryl ( polyglactic acid),dexon(polyglycolic acid), maxon(polyglyconate), PDS( poly dioxanone suture material ), monocryl, biosyn.Non absorbable suture materials are silk, polypropylene (prolene), polyethylene, cotton, linen, steel, polyester, polyamide, nylon.Reference : page 1172 SRB's manual of surgery 5th edition", 'role': 'assistant'}]