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: Surgery
[{'content': 'String sign of Kantor seen in? \nSelect and explain. \nA. Chrons discose, B. Ulcerative colitis, C. Both, D. None', 'role': 'user'}, {'content': "Answer: A \nExplanation: .Kantor's sign (String sign of Kantor): A radiological sign described in barium enema follow through in patients suffering from Crohn's disease. A string like configuration of contrast material through a filling defect is seen in the radiography. ref:SRB&;s manual of surgery,ed 3,pg no 1153", 'role': 'assistant'}]