Concept:The vertebrate circulatory system transports blood through the heart and three main types of blood vessels.
Explanation:The main components are the heart, arteries, capillaries, and veins.
Aorta and vena cava are specific examples of an artery and a vein, not general components.
Therefore, the correct general list is heart, arteries, capillaries, and veins.
Answer:A. heart, arteries, capillaries and veins