According to the diagram below, which animal class or classes have radial symmetry?
THE EVOLUTION OF ANIMALS 0
CHORDATES
AFECHINODERMS
ARTHROPODS
ANNELIDS
MOLLUSKS
RADIAL
SYMMETRY
DEUTEROSTOME
DEVELOPMENT
ROUNDWORMS
FLATWORMS
OPSEUDOCOELOM
CNIDARIANS
RADIAL
COELOM
SYMMETRY
PROTOSTOME DEVELOPMENT
THREE GERM LAYERS;
SPONGES
BILATERAL SYMMETRY
TISSUES
MULTICELLULARITY
SINGLE-CELLED ANCESTOR
O A. Arthropods only
B. Echinoderms and chordates
C. Arthropods, mollusks, and annelids
D. Cnidarians and echinoderms