Bivalves, compressed bodies enclosed by a shell consisting of two hinged parts. Bivalves include clams, oysters, cockles, mussels, scallops, and numerous other families that live in saltwater, as well as a number of families that live in freshwater.
D. The others answer only parts of it and d explains it as a whole
Assuming that you're talking about Sally ride, she was an astronaut that has took a photographic view of earth's surface from the space.
From up there , you can see the earth as a whole so it would be easier to observe every detail of its surface.
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