Question

Eustachian valve guards the opening of ...............

• A. coronary sinus
• B. coronary artery
• C. inferior venacava
• D. superior venacava

Hint:

The Eustachian valve prevents the backflow of blood from the right atrium into the inferior vena cava.

Answer 1

The Correct Option is C

Step 1: Understanding the anatomy.
The Eustachian valve is a valve located at the opening of the inferior vena cava into the right atrium. It prevents the backflow of blood into the vena cava.
Step 2: Analyzing the options.
(A) coronary sinus: Incorrect. The coronary sinus is a vein that returns deoxygenated blood from the heart muscle to the right atrium, but it is not guarded by the Eustachian valve.
(B) coronary artery: Incorrect. The coronary artery supplies blood to the heart muscle, but it is not associated with the Eustachian valve.
(C) inferior venacava: Correct. The Eustachian valve guards the opening of the inferior vena cava into the right atrium.
(D) superior venacava: Incorrect. The superior vena cava does not have an associated Eustachian valve.
Step 3: Conclusion.
The correct answer is (C) inferior venacava, as the Eustachian valve guards the opening of the inferior vena cava.