The next generation telephone is called Superphone or personal Communication Network (PCN). Your superphone goes wherever you go, in your pocket. You can use it in the street, in an aeroplane, a boat, or a taxi; you can call from anywhere on the globe to anywhere else. Calls travel at the speed of light, via satellites using ultraviolet, high-frequency wave bands and each communication is automatically billed to your account. This new phone is the size and shape of a billfold . You unfold it to use it., making it long enough to reach from your ear to your mouth. There is a miniaturized touch pad, on which to enter the number you are calling. There is also a tiny liquid crystal screen on which you can read weather, news or financial reports. These news items are constantly updated by the company that sells the service. Letter keys on the touch pad also allow you to use this electronic marvel as a computer or word processor. You can plug it into your large home or office computer in order to transfer any data that you feed in during a business trip. The PCN also stores any useful information of your own that you might need as you travel, such as the names, addresses and phone numbers of several hundred people, important meetings, flight details and so on. When you need information, you simply call it up on the screen. You can even use your PCN to activate electronically controlled equipment at home. For example, you could switch your oven on or off, start the sprinkler system in your garden during a dry spell, get your video recorder to record a show on television, turn off the central heating, and so on. All of this from thousands of miles away, perhaps from the back of a camel in the desert. Prototypes are already being trialed. In spite of the complex technology, they will be cheap because of the enormous sales that will be made. The Superphone system   _  .
has a very wide coverage of signals. deducts fees directly from users' bank account. offers a nearly free communicating service requires people to speak quickly
Question: The next generation telephone is called Superphone or personal Communication Network (PCN). Your superphone goes wherever you go, in your pocket. You can use it in the street, in an aeroplane, a boat, or a taxi; you can call from anywhere on the globe to anywhere else. Calls travel at the speed of light, via satellites using ultraviolet, high-frequency wave bands and each communication is automatically billed to your account. This new phone is the size and shape of a billfold . You unfold it to use it., making it long enough to reach from your ear to your mouth. There is a miniaturized touch pad, on which to enter the number you are calling. There is also a tiny liquid crystal screen on which you can read weather, news or financial reports. These news items are constantly updated by the company that sells the service. Letter keys on the touch pad also allow you to use this electronic marvel as a computer or word processor. You can plug it into your large home or office computer in order to transfer any data that you feed in during a business trip. The PCN also stores any useful information of your own that you might need as you travel, such as the names, addresses and phone numbers of several hundred people, important meetings, flight details and so on. When you need information, you simply call it up on the screen. You can even use your PCN to activate electronically controlled equipment at home. For example, you could switch your oven on or off, start the sprinkler system in your garden during a dry spell, get your video recorder to record a show on television, turn off the central heating, and so on. All of this from thousands of miles away, perhaps from the back of a camel in the desert. Prototypes are already being trialed. In spite of the complex technology, they will be cheap because of the enormous sales that will be made. The Superphone system   _  .
A. has a very wide coverage of signals.
B. deducts fees directly from users' bank account.
C. offers a nearly free communicating service
D. requires people to speak quickly
Answer: