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问题 选择题

下列不属于生态系统的是（　　）

A．一片热带雨林

B．一群羊

C．整个太平洋

D．一个养鱼池

答案

一片热带雨林、整个太平洋、一个养鱼池，既包括了所在的环境，也包括了环境中的所有生物，符合生态系统的概念，都属于一个生态系统；而一群羊只包括了生物部分的动物，没有其它生物，也没有环境部分，不能构成一个完整的生态系统．

故选B

单项选择题

Remote administration types are an example of one kind of (71) malicious software, the Trojan horse, or more simply Trojan. The purpose of these programs isn’t replication, (72) to penetrate and control. That masquerade as one thing when in fact they are something else, usually something destructive. There are a number of kinds of Trojans, including spybots, (73) report on the Web sites a computer user visits, and keybots or keyloggers, which record and report the user’s keystrokes in order to discover passwords and other confidential information.

RATS attempt to give a remote intruder administrative control of an infected computer. They work as (74) pairs. The server resides on the infected machine, while the client resides elsewhere, across the network, where it’s available to a remote intruder. Using standard TCP/IP or UDP protocols, the client sends instructions to the server. The server does (75) it’s told to do on the infected computer.

（71）处填（）。

A．nonviral

B．unviral

C．inviral

D．abviral
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单项选择题

家庭演唱卡拉OK时，家政服务员不要（）。

A、让客人先唱

B、自己争着唱

C、轻声伴唱

D、轻轻拍手
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