This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Medicine
[{'content': 'Prominent x descent in JVP is seen in all except \nSelect and explain. \nA. Cardiac tamponade, B. Atrial septal defect, C. Tricuspid regurgitation, D. Constrictive pericarditis', 'role': 'user'}, {'content': 'Answer: C \nExplanation: In tricuspid regurgitation x descent is absent. X descent is due to atrial relaxation during atrial diastole.', 'role': 'assistant'}]