This system permits blood to circulate and transport nutrients, oxygen, carbon dioxide, hormones, and blood cells.

a. Respiratory
b. Circulatory
c. Nervous

b. Circulatory

The correct answer is b. Circulatory.

The correct answer is b. Circulatory. The circulatory system is responsible for the transportation of nutrients, oxygen, carbon dioxide, hormones, and blood cells throughout the body. To determine the answer, you can recall basic knowledge about the functions of the respiratory, circulatory, and nervous systems.

a. The respiratory system is responsible for the exchange of gases, specifically oxygen and carbon dioxide, between the lungs and the bloodstream.

b. The circulatory system, also known as the cardiovascular system, is responsible for the circulation of blood throughout the body. It includes the heart, blood vessels, and blood. Its primary function is to deliver oxygen, nutrients, hormones, and other essential substances to the body's cells and tissues, while also removing waste products, including carbon dioxide.

c. The nervous system is responsible for transmitting signals and information between different parts of the body. It includes the brain, spinal cord, and nerves. While it plays a crucial role in coordinating bodily functions, it is not directly involved in the transport of nutrients, oxygen, carbon dioxide, hormones, or blood cells.

Therefore, based on the functions described, the correct answer is b. Circulatory.