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
Typical JVP finding in cardiac tamponade- 
Select and explain. 
A. Absent 'Y' descent, B. Prominant 'a' wave, C. Absent 'a' wave, D. Prominent 'Y' wave
A: Absent 'Y' descent
Answer: A: Absent 'Y' descent 
Explanation: None