Sandy: Hi, do you like running? Helen: I hardly ever exercise, because running is a little boring for me. How about you? Sandy: I stay in shape by running. I often run an hour each day. Helen: No wonder, you look very slim. ( )3..Why does Sandy look slim? A. Because she never exercises. B. Because she doesn’t run every day. C. Because she exercises by running an hour each day. D. Because run ning is a little boring.