This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Bile duct, Subject name: Surgery
[{'content': 'In a patient of cholangitis, surgical intervention was performed. In post-operative period, on 10th day this investigation was performed. What is the name of this investigation? \nSelect and explain. \nA. ERCP, B. MRCP, C. T-tube cholangiogram, D. PTC', 'role': 'user'}, {'content': 'Answer: C \nExplanation: The investigation is T-tube cholangiogram.', 'role': 'assistant'}]