This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Gall Bladder & Bile Ducts, Subject name: Surgery
[{'content': '5 days after CBD surgery there is a small leak. What will be the best treatment? \nSelect and explain. \nA. Ultrasound scan of the abdomen, B. Endoscopic cholangiography, C. Compute tomography, D. Magnetic resonance cholangiography', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. (a) Ultrasound guided aspirationRef: Blumgart 5/e p627* As per our Protocol- the first step is USG guided drainage - only for patients having persistent drainage we do ERCP and put Double Pig Tail Stenting.', 'role': 'assistant'}]