Which of the Following Animal Phyla is Distinguished by a Lack

Question

Which of the following animal phyla is distinguished by a lack of tissues?
A) Roundworms
B) Annelids
C) Echinoderms
D) Flatworms
E) Sponges

Accepted Answer

Sponges (phylum Porifera) are distinguished by their lack of true tissues and organs, unlike other animal phyla.