Which type of blood vessels carry blood that lacks oxygen to the heart?

Veins are responsible for carrying blood that is low in oxygen back to the heart. Unlike arteries, which transport oxygen-rich blood away from the heart to various parts of the body, veins collect deoxygenated blood from the capillaries and return it to the heart for reoxygenation. This process is essential for maintaining the body's circulatory system and ensuring that oxygen-depleted blood is effectively returned to the lungs, where it can release carbon dioxide and pick up fresh oxygen.

Capillaries serve as the exchange points between arteries and veins, facilitating the transfer of oxygen and nutrients to the tissues and collecting carbon dioxide and waste products. While venules are smaller vessels that collect blood from capillaries and channel it into veins, the primary role of veins is to transport this deoxygenated blood to the heart, making them the correct answer in this context.