The superior and inferior vena cava supply blood to which part of the heart?

The superior and inferior vena cava are responsible for transporting deoxygenated blood back to the heart from the body. Specifically, the superior vena cava collects blood from the upper parts of the body, including the head and arms, while the inferior vena cava collects blood from the lower parts, such as the legs and abdomen.

Both of these large veins empty their contents into the right atrium, which serves as the heart's receiving chamber for deoxygenated blood. From the right atrium, the blood will then flow into the right ventricle, where it is eventually pumped to the lungs for oxygenation. Therefore, the correct answer highlights the crucial role of the right atrium as the initial receiving site for blood from both the superior and inferior vena cava.