Little Tom down the street calls our dog "the keep dog". Zip is a sheep dog. But when Tom tries to say "sheep", it comes out "keep". And in a way Tom is right. Zip is always bringing things home for us to keep! I’ll tell you about some of them. Zip’s first present was a shoe. It was made of green silk. We didn’t know how Zip found the shoe. But after a moment Mary, my big sister, told me the shoe had a strange smell. I nodded(点头) and held my nose. "What do you think it is" "It smells like something for cleaning. I think someone tried to clean a spot(污点) off the shoe. Then he put it at the door to dry." "Along came Zip. And good-bye shoe!" I said. "We should take it back." "We can’t," said my sister. "We don’t know where Zip found it." "Maybe little Tom is right," Mary said. "Maybe Zip is a keep dog!\ Why did Mary say maybe Zip was a keep dog
A. Because the dog likes to give its owner presents.
B. Because the dog always brings things to its owner.
C. Because the dog always keeps things for its owner.