Multiple Choice
The fossil record of echinoderms
A) is sparse with few representatives.
B) shows echinoderms were a fairly modern group to arise.
C) indicates early echinoderms were sessile and pentaradial but had a bilateral ancestor.
D) suggests early echinoderms were free-swimming and bilateral but became sessile and pentaradial in recent times.
E) is a clear and detailed history of complex echinoderm evolution.
Correct Answer:

Verified
Correct Answer:
Verified
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