以下关于计算机网络拓扑的讨论中，哪一个观点是错误的______。
A．计算机网络拓扑通过网中结点与通信线路中的几何关系表示网络结构
B．计算机网络拓扑反映出网络中各实体间的结构关系
C．拓扑设计是建设计算机网络的第一步，也是实现各种网络协议的基础
D．计算机网络拓扑反映出网络中客户/服务器的结构关系
参考答案：D
解析： 计算机网络拓扑是通过网中结点与通信线路之间的几何关系表示网络结构，反映出各个实体间的结构关系。拓扑设计是建设计算机网络的第一步，也是实现各种网络协议的基础，它对网络的性能、系统可靠性与通信费用都有重大影响。
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| A 25-year-old student from Hubei was admitted into Tsinghua，China’s most famous university after an eight-year __1_ .Li Jun comes from a poor family in a small village of Hubei Province．He first __2__ going to college in the year 2000 __3__ he was admitted by a 1ocal school after __4_ from a secondary technical school at age 17．A __5_art student，he passed the exam again next year but __6__ school due to economic pressures in September 2002．Life seemed __7__but Li didn’t’t give in．He earned a ___8__ by working part time in Wuhan’s art rooms and tutoring students．But he never lost sight of his lifelong dream of __9__the Academy of Arts＆Design of Tsinghua University．Li _10__ the college entrance examination for five continuous years starting from 2003． __11 ，he missed making the cut by one mark last year． In 2008，his fifth try，Li’s efforts __12 .He finished the qualifying exam in his province and was finally admitted as a sculpture major into Tsinghua University．Every year．Li took art __13_ in Beijing and took exams from December to March．He then took cultural courses in his school till June．The rest of the year he spent on __14__work．Li said he hadn’t __15__ any money from his family since he graduated from the technical secondary school．Li said the reason he maintained for eight years was that he wanted to change his _16__ through knowledge。 __17 _by his contribution，Li Jun’s university ___18__ him 9000 yuan out of his tuition fees of 11450 yuan．An eight-year struggle may have come to an end for LiJun，but a new _19__ has now begun．Li said he would not worry about repaying loans at present．He wants to study well and ___20 _ more scholarships． | |||
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