【单选题】
集线器和路由器分别运行于OSI参考模型的___。
A. 数据链路层和物理层
B. 网络层和传输层
C. 传输层和数据链路层
D. 物理层和网络层
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答案
D
解析
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相关试题
【单选题】
在下面对OSI参考模型的数据链路层的功能特性描述中，哪一项是不正确的？___
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B. 数据链路层的主要任务是提供一种可靠的通过物理介质传输数据的方法
C. 将数据分解成帧，按顺序传输帧，并处理接收端发回的确认帧
D. Ethernet的数据链路层分为LLC和MAC子层，并在MAC子层使用CSMA/CD协议争用信道
【单选题】
下面属于TCP/IP协议族中网络互联层协议的是___。
A. IGMP、UDP、IP
B. IP、DNS、ICMP
C. ICMP、ARP、IP
D. FTP、IGMP、SMTP
【单选题】
Having practiced so many times, I feel very ___ of my ability to deliver the presentation successfully.
A. satisfied
B. incredible
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D. enthusiastic
【单选题】
The university decided to increase the ___ of the lecture hall, which has only 200 seats.
A. ability
B. capacity
C. facility
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【单选题】
Smart phones – with cameras and color screens – can ___ images and data using wireless network technology.
A. evolve
B. depart
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D. assure
【单选题】
Don’t take someone you get to know from the Internet to your house no matter how ___ he sounds.
A. bold
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【单选题】
This kind of exercise will ___ your creativity, renew your energy, and unlock your potential.
A. bind
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I’ll be happy to help you, ___ you won’t take up too much of my time.
A. as well as
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【单选题】
We teachers do not consider it wise to ___ our students with all sorts of exams, tests and quizzes.
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He makes his students ___ knowledge through various kinds of interesting activities.
A. study
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【单选题】
For years, scientists have debated the ___ dangers of building another nuclear plant after the terrible accident.
A. available
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It was a worthwhile attempt ___ it failed to achieve its purpose that we had hoped for.
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Travel in space can be very exciting; ___, it can also be boring and lonely at times.
A. so
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Politicians should not ___ in business affairs that might affect their political judgment.
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I wish to ___ a master’s degree in electric engineering after I graduate from college.
A. pledge
B. explore
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【单选题】
There is no greater importance ___ cultivating independence in children.
A. in
B. than
C. of
D. with
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He has made it very clear ___ we should observe the new rules.
A. what
B. which
C. those
D. that
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It was when I read his letter ___ I realized he had given me huge help.
A. that
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Don’t worry too much, Jane. Your son ___ home already. Let’s go back and check it out.
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【单选题】
___ they have written about the behaviors of animals is hardly anything new.
A. That
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No other drugs are as good as this one; it must have been based on a(n) ___ formula (配方).
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Mothers tend to be too ___ toward their children. They should let them see more of the worl D.
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The investigation ___ evidence of a large-scale illegal trade in wild birds.
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Poor Laura! I feel so sorry for her. When she fell, she hurt her arm and, ___, broke her glasses.
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【单选题】
Showing some sense of humor can be a(n) ___ way to deal with some stressful situations.
A. genuine
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【单选题】
It will be worth the efforts even if you fail; the rewards you ___ will be great.
A. reap
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【单选题】
He suggested transporting the supplies by air. But it is absolutely ___, for it will cost too much.
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【单选题】
The newspaper didn’t mention the ___ of the damage caused by the fire.
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【单选题】
Do you ___ her novels as serious literature or as mere entertainment?
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【单选题】
He doesn’t ___ of buying a house this year because the bank has refused to lend him any money.
A. afford
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【单选题】
If you don’t ___ cooking today, we can go out to eat at the new restaurant.
A. would like
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【单选题】
Bullying (恃强欺弱) can ___ a climate of fear and anxiety in school, and prevent students from focusing on their schoolwork.
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【单选题】
Science can now ___ many things which were thought to be mysterious by ancient people.
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The school has ___ many after-class activity groups for the pupils to make their spare time more colorful.
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When he was a small kid, he ___ from his peers because he could read fast and remember whatever he rea D.
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The fall in the number of deaths from heart disease is generally ___ improvements in diet.
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