What would be the best anatomical feature to look for to distinguish a gastropod from a chiton?

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Quizplus · Accepted Answer

The most distinctive anatomical feature to differentiate between gastropods and chitons is the number of shell plates. Gastropods have a single, coiled shell while chitons have eight separate shell plates on their dorsal surface. The other options listed (rasp-like feeding structure, production of eggs, and presence of a muscular foot) can be found in both gastropods and chitons.

What Would Be the Best Anatomical Feature to Look for to Distinguish