阅读理解
Navigation computers, now sold by most car-makers, cost $ 2,000 and up. No surprise, then, that they are most often found in luxury cars, like Lexus, BMW and Audi. But it is a developing technology — meaning prices should eventually drop — and the market does seem to be growing.
Even at current prices, a navigation computer is impressive. It can guide you from point to point in most major cities with precise turn-by-turn directions — spoken by a clear human-sounding voice, and written on a screen in front of the driver.
The computer works with an antenna (天线) that takes signals from no fewer than three of the 24 global positioning system (GPS) satellites. By measuring the time required for a signal to travel between the satellites and the antenna, the car''s location can be pinned down within 100 meters.
The satellite signals, along with inputs on speed from a wheel-speed sensor and direction from a meter, determine the car''s position even as it moves. This information is combined with a map database. Streets, landmarks and points of interest are included.
Most systems are basically identical. The differences come in hardware — the way the computer accepts the driver''s request for directions and the way it presents the driving instructions. On most systems, a driver enters a desired address, motorway junction or point of interest via a touch screen or disc. But the Lexus screen goes a step further: you can point to any spot on the map screen and get directions to it.
BMW''s system offers a set of cross hairs (瞄准器上的十字纹) that can be moved across the map (you have several choices of map scale) to pick a point you''d like to get to. Audi''s screen can be switched to TV reception.
Even the voices that recite the directions can differ, with better systems like BMW''s and Lexus''s having a wider vocabulary. The instructions are available in French, German, Spanish, Dutch and Italian, as well as English. The driver can also choose parameters for determining the route: fastest, shortest or no freeways (高速公路) , for example.
单选题
We learn from the passage that navigation computers ____________.
【正确答案】
C
【答案解析】推断题。题目询问从这篇文章中，我们可得知导航电脑_______。根据文章第1段“But it is a developing technology—meaning prices should eventually drop—and the market does seem to be growing (这是一项正在发展的技术，而且其市场还有很大的潜力)”，可推断，它将被越来越多的驾驶员接受。故选C项。
单选题
With a navigation computer, a driver will easily find the best route to his destination ____________.
【正确答案】
A
【答案解析】推断题。题目询问有了导航电脑，驾驶员只需_________就能轻易找出最佳的路线。根据文章第5段“On most systems，a driver enters a desired address，motorway junction or point of interest via a touch screen or disc(在大多数电脑系统中，驾驶员只需触摸屏幕输入想要去的地方即可)”，由此可推断，输入确切的目的地就是驾驶员惟一要做的事。因此，A项正确。
单选题
Despite their varied designs, navigation computers used in cars ____________.
【正确答案】
C
【答案解析】辨认事实题。题目询问尽管设计不同，汽车上的导航电脑_________。根据文章第5段“Most systems are basically identical. The differences come in hardware—the way the computer accepts the driver''s request for directions and the way it presents the driving instructions (大多数电脑系统的工作原理基本上是一致的，区别只是在于硬件——电脑接受驾驶员指令的方式和电脑输出驾驶指令的方式不同)”，因此，C项正确。
单选题
The navigation computer functions ____________.
【正确答案】
B
【答案解析】推断题。题目询问导航电脑的工作原理是_________。根据文章第4段“The satellite signals，along with inputs on speed from a wheel-speed sensor and direction from a meter，determine the car''s position even as it moves. This information is combined with a map database(卫星信号，连同车速传感器提供的车速数据和定向仪提供的方向一起确定汽车前进时的位置。这些信息同一个地图数据库相结合)”，故B项正确。
单选题
The navigation systems in cars like Lexus, BMW and Audi are mentioned to show ____________.