This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Medicine
[{'content': 'D-dimer is the sensitive diagnostic test for \nSelect and explain. \nA. Pulmonary embolism, B. Acute pulmonary oedema, C. Cardiac tamponade, D. Acute myocardial infarction', 'role': 'user'}, {'content': 'Answer: A \nExplanation: The sensitivity of the d-dimer is >80% for DVT (including isolated calf DVT) and >95% for PE. The d-dimer is less sensitive for DVT than for PE because the DVT thrombus size is smaller.A normal d-dimer is a useful "rule out" test. However, the d-dimer assay is not specific. Levels increase in patients with myocardial infarction, pneumonia, sepsis, cancer, and the postoperative state and those in the second or third trimester of pregnancy.Ref: Harrison\'s 19e pg: 1632', 'role': 'assistant'}]