Which vessels return blood from the lungs back to the heart?

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

Answer: (D)

The return flow from the lungs to the heart is through the pulmonary veins. After blood is oxygenated in the lungs, it travels via these veins and enters the left atrium, ready to be pumped out to the rest of the body. The pulmonary artery does the opposite—it carries deoxygenated blood from the right ventricle to the lungs for gas exchange. The aorta distributes oxygenated blood to the body, and the superior vena cava brings deoxygenated blood from the upper body back to the right atrium. So the vessels that return blood from the lungs back to the heart are the pulmonary veins.