Final answer:
The distribution of drugs within the body is carried out by the cardiovascular system, which includes the heart, blood vessels, and blood that transport various substances throughout the body.
Step-by-step explanation:
The distribution of drugs within the body is carried out through the cardiovascular system. This system, also known as the circulatory system, includes the heart, blood vessels, and blood. It is responsible for transporting materials to and from all the cells of the body, including oxygen, nutrients, hormones, and waste materials. Thus, when a drug enters the bloodstream, it is the cardiovascular system that moves it to the different parts of the body where it can exert its intended effect.