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': 'Which is the investigation of choice for recurrent sinusitis? \nSelect and explain. \nA. MRI, B. CT scan, C. X-ray PNS Waters view, D. X-ray PNS Cadwells view', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is'b'i.e., CT scanCT scan is the investigation of choice for recurrent sinusitis.", 'role': 'assistant'}]