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': "Typical JVP finding in cardiac tamponade \nSelect and explain. \nA. Absent 'Y' descent, B. Prominant 'a' wave, C. Absent 'a' wave, D. Prominant 'Y' wave", 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ref Harrison 19 th ed pg 1462 Cardiac tamponade is characterized by jugular venous diatenaiod ( increased JVP) with a prominent X descent but an ,absent Y descent.', 'role': 'assistant'}]