<prompt> Best investigation for pulmonary embolism ___:MRIVQ scanPlain CTCT angiography  <response>: Ans. D. CT angiographyPulmonary CT angiography MDCT is the best investigation for pulmonary embolism. The dye is injected through the intravenous route. VQ scan is done in pregnant females. Investigation of choice for an aortic aneurysm is CT angiography. 