关于Internet网络结构特点的描述中，错误的是( )。
A．局域网、城域网与广域网的数据链路层协议必须是相同的
B．局域网、城域网与广域网之间是通过路由器实现互联的
C．目前大量的微型计算机是通过局域网连入城域网的
D．Internet是一种大型的互联网
参考答案：A
解析：Internet是通过路由器实现多个广域网和局域网互联的大型网际网。在路由器互联的多个局域网中，通常要求每个局域网的数据链路层与物理层可以不同，但是数据链路层以上的高层要采用相同的协议。
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| A man went into a restaurant and sat down. A waiter went up to him and the man 1____ some of the most expensive dishes. The waiter brought them to the table and the man ate them 2____. Then a little boy came into the restaurant and sat at the man's 3____ The waiter came up and said to the man. "What would your little boy like to 4____, sir?" "Oh, just an ice cream. "The man told 5____ . Then he stood up and said to the waiter, "I'm just going out to buy a newspaper."He left the restaurant. The waiter gave the boy an ice cream. The boy ate it, and 6____ stood up and walked to the door. The waiter ran towards him. "Excuse me," he said, "but your father hasn't come 7____ and he hasn't paid for these dishes, not for your ice cream as well. " "I'm sorry,"the young boy said,"That has 8____ to do with me." "Oh, yes, it does, "the waiter said,"You will stay here 9____ your father comes back. " "He's not my father," the boy said. "I don't know who he is. He asked me 10____ I liked ice cream, and I said yes. Then he told me to come into the restaurant at 2 o'clock. |