The right option is; C. Double loop
Humans have double loop type of circulatory system.
The double loop circulatory system is a circulatory system that is composed of two separate loops which are; the systemic loop, and the pulmonary loop in which blood circulates. The systemic loop is the flow of oxygen rich blood from the heart to all the cells in the body. This loop supplies oxygen and nutrients, and moves carbon dioxide back to the heart, while the pulmonary loop is the flow of deoxygenated blood from the heart to the lungs. The carbon dioxide from the blood is exchanged for oxygen within the lungs after which the blood is moved back to the heart.
