阅读下列短文，从每题所给的四个选项（A、B、C、和D）中，选出最佳选项，并在答题卡上将该项涂黑。
A
Shopping centers，stadiums and universities may soon have a new tool to help fight crime.
A California company called Knightscope says its robots can predict and prevent crime. Knightscope says the goal is to reduce crime by half in areas the robots guard.
William Santana Li is the chief executive officer of Knightscope. He says，"These robot security guards will change the world. Our planet has more than seven billion people on it. It's going to quickly get to nine billion people. The security equipment that we have globally is just not going to develop that fast. The company's Autonomous Data Machines can become the eyes and ears of law enforcement（执法）."
"You want them to be machines plus humans. Let. the machines do the heavy and sometimes dangerous work and let the humans do the strategic decision-making work，so it's always working all together."
The machines do not carry weapons but they have day and night video cameras which are able to turn 360 degrees and can also sense chemical and biological weapons.
Some people may become concerned about their privacy, especially in connection with the video recordings. Some people may worry that such recordings will appear on the Internet. Eugene Volokh, a law professor at the UCLA School of Law, says the machines have to be used in the right way and it will be interesting to see how state laws deal with this kind of video.
William Santana Li says there is a long waiting list for the robots in the US. Workers in the company are working overtime to meet the demands of the market. At least 25 other countries are also interested in these robot security guards.
21. What can this new tool do for humans?
A. Make strategic decisions.
B. Keep watching day and night.
C. Carry heavy weapons.
D. Stop crime autonomously.
22. Why are some people worried about the new robots?
A. Their privacy may be let out.
B. The robots are very expensive.
C. Robots will replace humans.
D. They will be out of work soon.
23. Which of the following can be the best title of the text?
A. Robots Are Becoming More Popular
B. Robots Contribute a Lot to the World
C. Robots Are in Great Demand Now
D. Security Robots Could Help Cut Crime
【答案】21. B 22. A 23. D
【解析】
【分析】本文是一篇说明文，主要介绍了一款新型的预防犯罪的机器人保安。
【21题详解】
细节理解题。根据第五段"The machines do not carry weapons but they have day and night video cameras which are able to turn 360 degrees and can also sense chemical and biological weapons（这些机器不携带武器，但它们有昼夜摄像机，可以360度旋转，还能感知化学武器和生物武器）"可知，这种机器人能够日夜不停地执勤站岗。故选B。
【22题详解】
细节理解题。根据倒数第二段中的"Some people may become concerned about their privacy...will appear on the Internet"可知，一些人担忧这种机器人所携带的摄像机会记录其隐私，其隐私有可能会被泄露。故选A。
【23题详解】
主旨大意题。结合全文内容尤其是文章第一段可知，本文主要介绍了一种新型的预防犯罪的机器人保安。故选D。
