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: Radiology
[{'content': 'Best investigation to diagnose a hydatid cyst in liver is ? \nSelect and explain. \nA. Ultrasound, B. CT-scan, C. MRI, D. MRCP', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is 'b' i.e., CT-scanFor hydatid cyst1st line investigation - UltrasoundInvestigation of choice - CT-scan", 'role': 'assistant'}]