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': 'Triad of renal colic, swelling in loin which disappears after passing urine is\ncalled \nSelect and explain. \nA. Borchardt’s triad, B. Dietel’s crisis, C. Beck’s triad, D. Stuffer’s triad', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]