The vessel draining deoxygenated blood from the lower body into the heart is the:

• A. Aorta
• B. Pulmonary artery
• C. Superior vena cava
• D. Inferior vena cava

Answer: (D)

In the circulatory system, veins return blood to the heart. The large vein that drains the lower body and delivers deoxygenated blood into the right atrium is the inferior vena cava. It collects blood from the legs, pelvis, and abdomen (via iliac veins and other tributaries) and channels it into the right atrium, setting up the path for the blood to move to the lungs for oxygenation. By contrast, the aorta carries oxygen-rich blood away from the heart to the body, the pulmonary artery carries deoxygenated blood from the right ventricle to the lungs, and the superior vena cava drains the upper body into the right atrium.