Which type of blood vessel is responsible for returning blood to the heart?

Veins are the blood vessels responsible for returning deoxygenated blood back to the heart after it has circulated throughout the body. They play a crucial role in the circulatory system by carrying blood at a lower pressure compared to arteries. Veins have valves that help prevent the backflow of blood, ensuring that it moves in one direction toward the heart.

In contrast, arteries transport oxygen-rich blood away from the heart to the tissues of the body, whereas capillaries are small blood vessels where the exchange of oxygen, carbon dioxide, and nutrients occurs between blood and the body's cells. The aorta, on the other hand, is the largest artery in the body that carries oxygenated blood from the heart to the rest of the body, not returning blood to the heart. Thus, the role of veins is specifically aligned with the task of returning blood to the heart, making them the correct answer in this context.