Answer:
All of the above
Step-by-step explanation:
This is because lack nerves, muscles, internal organs including brain and that is why they are refered to simplest animals. Sponges are multicellular animals that belong the phylum porifera and clade metazoa. Water current from the water bodies carry food to sponges and the same water current take away waste products. They have pores that allow water to channel through their bodies.