Both echinoderms and chordates are deuterostomes. This means that

A) they have a similar development in their embryonic stages.
B) they both have eyes with retinas.
C) they both start with radial symmetry in their early embryonic stages.
D) they both use calcium-based endoskeletons.
E) they are both invertebrates.

Deuterostomes

A major division of the animal kingdom in which the anus develops from the first opening in the embryo, followed by the mouth.

Echinoderms

Marine animals characterized by radial symmetry and a unique water vascular system, which includes species such as sea stars, sea urchins, and sea cucumbers.

Embryonic Stages

Phases of development that an embryo goes through from fertilization to birth.