Multiple Choice
Echinodems
A) have larvae that are radially symmetrical and free-swimming.
B) are marine animals that have a five-rayed symmetry and no head.
C) have a water vascular system of radial muscles that pump water through the animal.
D) have dipleurula larva derived from a double-layered balstula.
E) have an external skeleton composed of spicules which give it its 'spiny skin'.
Correct Answer:

Verified
Correct Answer:
Verified
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