Which system consists of the heart, arteries, blood, and veins, responsible for distributing blood and nutrients throughout the body?

The cardiovascular system is the correct answer because it encompasses the heart, arteries, blood, and veins, which work together to pump and circulate blood throughout the body. This system is essential for delivering oxygen and nutrients to tissues, as well as removing waste products such as carbon dioxide. The heart acts as the central pump, while the arteries carry oxygen-rich blood away from the heart and veins return deoxygenated blood back to it. This continuous process is crucial for maintaining homeostasis and overall health.

In contrast, the respiratory system primarily focuses on gas exchange, bringing oxygen into the body and expelling carbon dioxide. The nervous system is responsible for transmitting signals throughout the body to regulate bodily functions and respond to stimuli. The endocrine system involves glands that secrete hormones into the bloodstream, affecting various physiological processes, but does not primarily deal with the circulation of blood itself. Understanding these distinctions highlights why the cardiovascular system is pivotal in maintaining the body's nutrient and oxygen supply.