Which of the following list of features describes the molluscs and bivalves but not the annelids?
A. Reduced cephalization, contain a muscular foot and a mantle, may possess a hard outer shell.
B. Lack of cephalization, contains circular muscles that enable them to move, may possess a hard outer shell, and have a complete digestive system.
C. Lack of cephalization, every member of the group will have a hard outer shell as well as a complete digestive system.
D. Presence of cephalization, contain a muscular foot and a mantle, may possess a hard outer shell and have a complete digestive system.
E. None of these lists describes the molluscs and bivalves but not the annelids.
Answer: A
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