Best investigation when there is clinical suspicion of pulmonary embolism in a patient is-

Answer is B (Multidetector CT Angiography): For patients with strong clinical suspicions/high likehood of DVT. Imaging tests are obligatory. CT scan with intravenous contrast (Multidetector CT Angiography) is the test of choice for the diagnosis of PE. Invasive catheter based pulmonary Angiography is highly specific but reserved for patients with unsatisfactory chest CT or those who require an interventional procedure like catheter directed thrombolysis or embolectomy.