This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.V.S, Subject name: Medicine
Giant&;a&;wave in JVP is seen in- 
Select and explain. 
A. Junctional rhyth, B. Tricuspid regulation, C. Complete hea block, D. Tricuspid stenosis
D: Tricuspid stenosis
Answer: D: Tricuspid stenosis 
Explanation: in Tricuspid stenosis The jugular veins are distended, and in patients with sinus rhythm there may be giant a waves. The v waves are less conspicuous, and because tricuspid obstruction impedes RA emptying during diastole, there is a slow y descent. In patients with sinus rhythm there may be prominent presystolic pulsations of the enlarged liver as well. ( Harrison&;s principle of internal medicine,18th edition,pg no.1946 )