What does the circulatory system do?
A. Sends hormones to the body
O B. Moves blood around the body
C. Brings oxygen into the body
O D. Defends against invaders

B

Explanation:

The circulatory system is made up of blood vessels that carry blood away from and towards the heart. Arteries carry blood away from the heart and veins carry blood back to the heart. The circulatory system carries oxygen, nutrients, and hormones to cells, and removes waste products, like carbon dioxide.

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