What is the main role of arteries in the circulatory system?

The main role of arteries in the circulatory system is to carry oxygenated blood away from the heart to the tissues and organs throughout the body. This is essential for delivering the oxygen and nutrients that cells need for energy and function. Arteries are designed with thick, elastic walls that can withstand the high pressure generated by the heart as it pumps blood.

In contrast, the other options describe functions that are not the primary role of arteries. While option A refers to veins that carry unoxygenated blood back to the heart, option B describes the role of capillaries, where the exchange of gases, nutrients, and waste occurs between blood and tissues. Option D pertains to veins, which are responsible for returning deoxygenated blood to the heart. Thus, the unique role of arteries in transporting oxygen-rich blood is clearly articulated in the correct choice.