Shellfish choices include clams, which are a type of mollusk with two shells connected by a hinge. Clams are found in both saltwater and freshwater habitats, and can be eaten raw, steamed, or fried. Other shellfish choices include oysters, mussels, and scallops. Oysters are also mollusks, and are usually found in saltwater habitats. Mussels are bivalve mollusks that live in both saltwater and freshwater habitats, and are often steamed or boiled. Scallops are also bivalve mollusks, and are usually found in saltwater habitats. They are often served grilled, fried, or steamed.