Respuesta :
The blood circulates throughout the body because of the contraction and relaxation of the heart which pushes the blood throughout the body. So, the correct option is B.
What is the circulatory system?
The circulatory system is a specialized system for the circulation of blood throughout the body. This blood is rich in nutrients obtained from the digestive system after digestion and oxygen obtained from the respiratory system after breathing.
The circulatory system is like an industrial pipeline system in which a pump or motor, pipes and the component flow through the pipes.
The blood vessels represent the pipes. There are two types of blood vessels, the arteries and the veins which carry oxygenated and deoxygenated blood respectively.
The blood is the component flowing through the blood vessels. The blood is a liquid tissue, in which the liquid component is called the plasma and the cellular component is represented by three types of cells. These are the red blood cells, white blood cells and platelets. The nutrients flow freely in the blood plasma and oxygen is carried by the Red blood cells.
The heart is the pump of this system, it contracts to push blood through the blood vessels and relaxes to allow blood into its chambers. The human heart has four chambers.
Therefore, the correct option is B.
Read more about the circulatory system, here https://brainly.com/question/10103458
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