Which vessels in the lungs carry oxygenated blood back to the heart?

• A. Arteries
• B. Veins
• C. Capillaries
• D. Bronchi

Answer: (B)

The vessels that carry oxygenated blood back to the heart from the lungs are the veins, specifically the pulmonary veins. After the process of gas exchange in the lungs, where carbon dioxide is released and oxygen is absorbed, the oxygen-rich blood is collected by these veins. The pulmonary veins transport this oxygenated blood to the left atrium of the heart, where it is then pumped out to the rest of the body.

In the context of the other choices, arteries carry deoxygenated blood away from the heart to the lungs for oxygenation, while capillaries are the tiny blood vessels where the exchange of oxygen and carbon dioxide occurs but do not themselves transport blood back to the heart. The bronchi are air passages that direct air to the lungs and do not play a role in blood circulation. Thus, identifying veins as the correct answer highlights their essential role in returning oxygen-rich blood to the heart.