The Most Ancient Deuterostomes Are

Question

The most ancient deuterostomes are
A)annelids.
B)echinoderms.
C)mollusks.
D)arthropods.

Accepted Answer

The most ancient deuterostomes are echinoderms, which include animals such as sea stars and sea urchins. This group is characterized by several key features, including radial symmetry and a unique water vascular system that is used for movement and feeding. Annelids, mollusks, and arthropods are all protostomes, which represent a different evolutionary lineage.