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': '43 year old patient it has undergone cholecystectomy. She has developed bile leak. What is the preferred next step \nSelect and explain. \nA. HIDA scan, B. ERCP, C. Open CBD exploration, D. Observation', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Hida scan is helpful in diagnosing bile leak or obstruction but ERCP is both diagnostic and therapeutic.', 'role': 'assistant'}]