Which of the following are the three major types of blood vessels?

The three major types of blood vessels in the circulatory system are arteries, capillaries, and veins. Arteries are responsible for carrying oxygenated blood away from the heart to the tissues of the body, with the exception of the pulmonary artery, which carries deoxygenated blood to the lungs. Capillaries are the smallest blood vessels where the exchange of gases, nutrients, and waste products occurs between the blood and the tissues. They connect arteries and veins, facilitating this crucial exchange. Veins transport deoxygenated blood back to the heart, completing the cycle of blood circulation.

In the context of the other options, lymphatics refers to a different system involving lymphatic vessels and does not classify as one of the major blood vessel types. The heart, while essential to the circulatory system, is not a blood vessel but rather a muscular organ that pumps blood throughout the body. Thus, the only combination that correctly identifies the three principal types of blood vessels is arteries, capillaries, and veins.