Earthworms like the one shown have a simple heart that
pumps blood throughout the body.

b

Explanation:

Explanation:

Option A and B.

Organ system and tissues.

Explanation:

Earthworm is a segmented worm that belong to the phylum annelids. Earthworm has a close circulatory system just as human beings which means their blood circulate through a closed network of vessels which are connective tissues. Earthworm has a structure of 5 hearts and they are called aortic arches which are organ systems. These pump blood into network of vessels and it's flow through the body. From there, the blood move to dorsal blood vessel which send blood to the front of the Earthworm, then to the ventral blood vessel which send blood to the posterior. At the intestines, there are lateral vessels which carry nutrients away from the gut and to the body.