【正确答案】 D

【答案解析】[听力原文]
CATV is a short way of saying "community antenna television." But "cable television" is the term most people use. Cable television allows viewers to receive TV programs that they cannot pick up with their regular antennas.
Television signals do not follow the curve of the earth. They travel in straight lines in all directions. Signals from a TV station move toward the horizon and then go into space. If you live only a few miles from a station, you may not get any picture at all.
CATV began in 1948. People in places far from TV stations shared the cost of putting up high antennas. A community antenna was usually placed on a hill, a mountain, or on a high tower. The antenna picked up TV signals and fed them into a small local station. From the station, thick wires called cables ran out to nearby homes. Each person using the cable paid a monthly charge.
CATV worked well, and soon new uses were found for it. Local stations could feed programs into empty channels that were not in use. People along the cable could have local news, weather reports, and farm and school news at no extra charge.
Today, cable television has moved into cities. It brings in extra programs that city viewers with regular antennas cannot see. It is also used in many classrooms throughout the country.

What does the speaker say about television signal?

[解析] 短文提到，电视信号不沿地球的曲线传播，而沿直线向四周传播，故D正确。
A、B短文中未提及，而C与短文意思相悖。

【正确答案】 A

【答案解析】[听力原文]
What should people do if they used the cable?

[解析] 短文提到，有线电视用户要每月交费，故A正确。
①四个选项的中心词都是charge，差别在于表时间的修饰语(monthly/yearly等)，听音时要留意收费的频率(方式)，不难得出正确答案。②其他选项均与短文意思不符。

【正确答案】 B

【答案解析】[听力原文]
What happens after cable television has moved into cities?

[解析] 短文提到，有线电视进入城市后，给城市观众带来了普通天线无法提供的额外节目，故B正确。
短文说的是，有线电视在许多教室里得到应用，但没有说是在全部教室，故A错误；C、D未提及，排除。