《计算机专业英语》第13章在线测试

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第一题、单项选择题(每题1分，5道题共5分)

?1、Confidentiality of the message is not enough in a secure communication; ＿＿＿＿＿＿＿＿ is also needed. The receiver needs to be sure of the sender’s identity.

A、encryption

B、authorization

C、authentication

D、encapsulation

?2、The data, when they are not encrypted, are called ＿＿＿＿＿＿＿＿.

A、plaintext

B、ciphertext

C、hypertext

D、context

?3、A virus is a ＿＿＿＿＿＿＿＿＿ .

A、beast

B、computer

C、bad man

D、program

?4、Many viruses go resident in the memory like a ( ).

A、.exe file

B、.com file

C、tsr program

D、data file

?5、Now, about ( ) different viruses account for all the viruses that actually spread in the wild.

A、30

B、150

C、1800

D、3000

第二题、多项选择题(每题2分，5道题共10分)

?1、Viruses all have two phases to their eｘecution, the ( ) and the ( ).

A、infection phase

B、del＿ete phase

C、attack phase

D、creaｔe phase

?2、( ) maybe a certain cause that some viruses infect upon.

A、a day

B、a time

C、an external event on your PC

D、a counter within the virus

?3、Many viruses do harmful things such as ( ).

A、deleting files

B、simulating typos

C、slowing your PC down

D、changing random data on your disk

?4、If a virus simply reproduce and have no cause for an attack phase, but it will still ( ) without your permission.

A、stealing storage

B、pilfer CPU cycles

C、del＿ete files

D、play music

?5、Some viruses, with no attack phase, often damage the programs or disks they infect because they ( ).

A、have bugs in them

B、contain poor quality code

C、steal storage

D、show messages on your screen

第三题、判断题(每题1分，5道题共5分)

?1、Computer security is a branch of technology known as information security as applied to computers.

正确

错误

?2、Michelangelo is a file sector.

正确

错误

?3、Computer virus is remote from us.

正确

错误

?4、Computer virus may affect the your phisical health .

正确

错误

?5、The author thinks that understanding how an attacker approaches your computer system can help you protec