AP BIOLOGY

Detailed explanation-1: -Crustaceans are aquatic animals that have jointed legs, a hard shell and no backbone, such as crab, crayfish, lobster, prawns and shrimp. Most molluscs have a hinged two-part shell and include clams, mussels, oysters and scallops, as well as various types of octopus, snail and squid.

Detailed explanation-2: -The molluscan shellfish relevant in human diet are gastropods (including abalones, limpets, land and marine snails, whelks), bivalves (including oysters, mussels, scallops) and cephalopods (including squids, octopuses).

Detailed explanation-3: -Answer and Explanation: The animal that is not a crustacean is the C) Grasshopper. Grasshoppers are insects, belonging to class Insecta. Crustaceans are members of class Crustacea, and this includes lobsters, crabs and crayfish.

Detailed explanation-4: -Crustaceans include crabs, lobster, crayfish, shrimp and prawn. Mollusks include squid, octopus, mussels, snails, clams, oysters, abalone and scallops.