Name the three vessels that deliver oxygen-poor blood to the right atrium

Superior vena cava, Inferior vena cava, Coronary sinus.

Explanation:

Superior vena cava, Inferior vena cava and Coronary sinus deliver the oxygen poor blood to right atrium.

Superior vena cava delivers the deoxygenated blood from the upper half of the body to the right atrium.

Inferior vena cava delivers the deoxygenated blood from the lower half of the body to right atrium.

Coronary sinus delivers the oxygen-poor blood from the heart muscles to the right atrium.