The embryonic nervous systems of peanut worms (Sipuncula) and spoon worms (Echiura) show that these worms ________
A) are descended from segmented ancestors
B) have appendages that are homologous with arthropod appendages
C) do not express Hox genes during development
D) are similar to each other because of homoplasy
E) are surprisingly closely related to vertebrates
A
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