An organism might rely on the diffusion of oxygen and carbon dioxide through their outer body covering if it a. thin and lives on land. b. small and lives in water. c. protected by a shell. d. a vertebrate chordate

That organism might rely on the diffusion of oxygen and carbon dioxide through their outer body covering if it's : B. small and lives in water
Organisms that live in water cannot get their oxygen with the same process like we did on the land. They need the process of diffusion in order to do it

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