This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.V.S., Subject name: Radiology
[{'content': 'Best investigation for pulmonary embolism ___: \nSelect and explain. \nA. MRI, B. V/Q scan, C. Plain CT, D. CT angiography', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans. D. CT angiographyPulmonary CT angiography /MDCT is the best investigation for pulmonary embolism. The dye is injected through the intravenous route.* V/Q scan is done in pregnant females.* Investigation of choice for an aortic aneurysm is CT angiography.', 'role': 'assistant'}]