Answer:
The correct answer is class bivalvia.
Step-by-step explanation:
The phylum Mollusca comprises seven classes, that is, Aplacophora, Bivalvia, Monoplacophora, Gastropoda, Cephalopoda, Scaphopoda, and Polyplacophora. The mollusk is categorized by the existence of a flap-like tissue over the visceral mass called the dorsal mantle that produces a space called the mantle cavity. The visceral mass comprises all the internal organs of these species. The mantle cavity, that is, produced within the mantle forms in an autonomous way from the coelomic cavity.