Answer:
False, it is only represented by one class: Crinoidea (sea lilies).
Step-by-step explanation:
Echinoderms (phylum Echinodermata) are marine organisms that comprises more than 6,000 species. These animals are deuterostomes that are differentiated to have an ambulacral vascular system and a pentameric symmetry. Echinoderms are divided in the following classes: 1- Ophiuroidea (snake stars), 2-Asteroidea (sea stars), 3-Crinoidea (sea lilies), 4-Holothuroidea (sea cucumbers) and 5-Echinoidea (sea urchins), which can be easily distinguished by anatomical and ecological characteristics.