Final answer:
The most commonly affected coronary cusp in sinus of Valsalva aneurysm is the right coronary cusp.
Step-by-step explanation:
The correct answer is A. Right coronary cusp.
In a sinus of Valsalva aneurysm, the most commonly affected coronary cusp is the right coronary cusp. The sinus of Valsalva is a small dilation or pouch in the wall of the aorta just above the aortic valve. Aneurysms in the sinus of Valsalva can lead to complications such as aortic valve regurgitation or compression of nearby structures.
References: Coronary Circulation