Which of the following blood vessels carries deoxygenated blood?

The story behind the answer

Pulmonary artery is correct because it carries deoxygenated blood from the right ventricle to the lungs, where carbon dioxide is exchanged for oxygen. In contrast, the pulmonary vein brings oxygenated blood back to the left atrium, the aorta distributes oxygen-rich blood to the body, and the coronary arteries supply the heart muscle with oxygenated blood.

Helpful tip: arteries are defined by direction (away from the heart), not by oxygen content. The pulmonary artery is the key exception that carries deoxygenated blood; the pulmonary vein is the exception that carries oxygenated blood toward the heart. Think “lungs are the laundry”: dirty blood goes out via the pulmonary artery, clean blood returns via the pulmonary vein.