Coming soon to your TV: views of the hottest live basketabll plays from any seat in the stadium. What a better look at that thre

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问题    Coming soon to your TV: views of the hottest live basketabll plays from any seat in the stadium. What a better look at that three-point shot? Call for a replay from behind the basket. Or better yet, follow the "view" of the ball as it goes through the net.
   While watching, you might use a built-in speakerphone to talk with a fan in the stands. Sounds impossible? It won’ be when the television industries combine to create digital TV—machines that receive, send, store and manipulate TV programs the way computers now manipulate other data.
   Industry and government representatives recently reached an agreement on how this technology will take place. New digital TVs that allow current TVs to receive digital signals may hit store shelves by next spring.
   To understand how the digital revolution will change the way you watch TV, it helps to know how TVs work now. Today, TV networks such as CBS and Fox broadcast TV show as analog electrical signals. These signals travel via the airwaves, satellites, or cable as a continuous stream of electromagnetic energy (like light and radio waves). But this system leaves a lot of room for error. The main problem is that interference can change the voltage of the signal as it travels. This may result in a distorted of miscolored picture. If we send out the signal in a form that is nearly free from interference -- binary code, pictures and colors are not distorted.
   You will need to buy a new TV to receive these signals. And the new sets may cost 1, 000 US dollars more than today’s TVs. But they will come with other benefits that may make the price worthwhile. For one thing, the screens will be wider, like movie screens. In addition, the color will be richer. And you will also get digital CD-quality sound.
   Besides these benefits, digital TVs can offer you much wider choice of programs. Digital data can expand TV choices because computers can compress digital signals. Broadcasters will be able to send out six times as much as information on the same "channel".
The following qualities are mentioned in the passage EXCEPT ______?

选项 A、interference-free pictures
B、a richer color
C、a wider screen
D、good reception of signals

答案D

解析
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