This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General Management of Wounds, Subject name: Surgery
[{'content': 'Catgut is prepared from submucosal layer of the intestine of: \nSelect and explain. \nA. Cat, B. Sheep, C. Human being, D. Rabbit', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. (b) Sheep(Ref: Bailey 261e p37-38)Catgut points:* Discovered by John Hunter* Plain catgut is derived from Sheep submucosa of intestine* Plain catgut loses its strength by 50% in 3 days- Complete strength lost by 15 days and absorbed in 60 days* Isopropyl alcohol is used to preserve catgut.', 'role': 'assistant'}]