阅读短文，选择正确的答案。

A Wolf in Sheep's Clothing

A wolf (狼) wanted to eat the sheep, but he was afraid of the vigilant shepherd (牧羊人) and his dogs. One day the wolf found the skin of a sheep. He put it on and walked among the sheep. A lamb thought that the wolf was its mother because his skin looked like hers. So itfollowedthe wolf. Soon after they had left the dogs, the wolf came at the lamb and ate it up.