在OSI参考模型中，路由器、交换机Switch、集线器Hub实现的最高功能层分别是（    ）。

(单选题)—Sarah is chosen as the guide for the Fashion Show.— Great! (单选题)His ideas are invariably condemned as ( ) by his colleagu (单选题)To my horror, I saw, ( ) my father's shoulder, a gorilla. (单选题)—Tom, where do you work?—I work in a shop ( ) sells diffe (单选题)— ( ) you ( ) the editor at the airport?— No, he ( (单选题)( ), the more severe the winters are. (单选题)( ) he wanted to go out with his friends at the weekend, (单选题)Mr. Wells, together with all the members of his family, ( (单选题)Had Judy been more careful on the maths exam, she ( ) mu (单选题)Stan Lee, an outstanding comic-book writer, created plenty o