please help me to find out the what is geography? A. the study of the environment. B. the study of rocks. C. the study of geology. D. the study of the environment and man. And explain your aanswer​

In shallow water at the beach, manuel saw an animal whose body was protected by hard plates. its body also had radial symmetry. the animal pumped water into its tube feet to move. which invertebrate group does this animal belong to? a. mollusks b. echinoderms c. sponges d arthropods