Which vessel carries oxygenated blood from the lungs to the left atrium?

• A. Left Pulmonary Vein
• B. Right Pulmonary Artery
• C. Pulmonary Trunk
• D. Superior Vena Cava

Answer: (A)

The concept here is how oxygenated blood returns from the lungs to the heart. After the lungs oxygenate the blood, it travels back to the heart through the pulmonary veins. The left atrium is the chamber that receives this oxygen-rich blood, and the vessel that brings it from the lungs specifically to the left atrium is the left pulmonary vein. From the left atrium, blood moves to the left ventricle to be pumped out to the body.

In contrast, the pulmonary trunk and pulmonary arteries carry blood away from the heart to the lungs and are part of the system that transports deoxygenated blood. The superior vena cava brings deoxygenated blood from the upper body back to the right atrium. The pulmonary veins are the exception to the usual rule that veins carry deoxygenated blood; in the pulmonary circulation they return oxygenated blood to the heart.