This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: G.I.T, Subject name: Medicine
[{'content': "Appendicectomy is protective in \nSelect and explain. \nA. Irritable bowel syndrome, B. Ulcerative colitis, C. Crohn's disease, D. Caeliac sprue", 'role': 'user'}, {'content': 'Answer: B \nExplanation: There is a protective effect of the previous appendectomy with confirmed appendicitis (reduction of 13-26%), paicularly at a young age, on the development of UCRef: Harrison 19e pg: 1947', 'role': 'assistant'}]