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': 'Critically ill patient recovering from a surgery develops right upper quadrant pain. What is the probable diagnosis \nSelect and explain. \nA. calculous cholecystitis, B. Acalculous cholecystitis, C. Empyema of gallbladder, D. Porcelain gallbladder.', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Acalculous cholecystitis is found in critically ill patients and patients recovering from major surgery, trauma and burns.', 'role': 'assistant'}]