This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General anatomy, Subject name: Anatomy
[{'content': 'Pulsus paradoxus is seen in all except \nSelect and explain. \nA. IPPV, B. COPD, C. Cardiac tamponade, D. Constrictive pericarditis', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ref Harrison 19 th ed pg 1573 t 288-2 Pulsus paradoxus is not a feature of IPPV. Pulsus paradoxus may be seen in association with cardiac tamponade, constrictive pericarditis and COPD', 'role': 'assistant'}]