【正确答案】
B
【答案解析】[听力原文]
At first, computers don"t seem like a revolution. In the 1940s, a single computer with the power of a basic PC today could be the size of a Greyhound bus, and needs the same amount of power as a small town. Many people believe that only a few computers will ever be sold. But then they start to reveal their power. In the 1960s computers are used by universities to achieve previously unthinkable calculations. And from the 1970s onwards, corporations use them to replace thousands of manual clerks. Cold War superspending helps fund computer development, helping companies like IBM to become massive corporations. But it"s not corporations or the government that create the next computer revolution. 1976, a garage in Northern California, two computer hobbyists, Steve Jobs and Steve Wosneak create the world"s first practical personal computer. The original kind of pioneers of the digital revolution. In a sense, they were building computers for themselves, for ordinary people like them. They weren"t particularly wealthy. They weren"t working for large organizations. They just were tinkers. Soon competitors bring out their own machines. When IBM launched their PC, it ups the game. Computers are changing fast. Along came the mouse and along came pictures on the screen. That kind of competition is really where innovation comes from. The apple II of 1980 has more computing power than was used in the entire Apollo moon landing program. Personal computers become more powerful, more popular.
There are just 300,000 PCs in 1980. By 1990, there are over 67 million. That year, Microsoft sales alone topped $1 billion. But the true power of computers is yet to be realized. Only when they start to talk to each other, will the computing revolution be complete.
Why many people believe that only a few computers will ever be sold?