Question

What is the main function of the circulatory system in multicellular organisms?

A. to bring oxygen into the lung

B. to put carbon dioxide into all blood vessels

C. to expel waste products from the body

D. to transport materials throughout the body

Answer 1

D. To transport materials throughout the body. Most of the choices here could be the answer, but D is the main function of the circulatory system.
It is the transportation system for your body. The circulatory system carries chemicals to all points in your body. The fluids also carry waste products and dissolved gases for your cells.

Answer 2

thanks