Mollusks (phylum Mollusca) are coelomates with three main body parts: the muscular foot, a visceral mass with its internal organs, and a mantle. Having more than 100,000 species, they have a number of unique differences.
Which one of the following is incorrect concerning molluscs?
A. Some members of the Phylum Mollusca are filter feeders.
B. All members of the Phylum Mollusca have a radula.
C. Not all members of the Phylum Mollusca have an external shell.
D. Some members have direct development and do not produce larval stages.