单项选择题

The Science of the Future

Until recently, the "science of the future" was supposed to be electronics and artificial intelligence. Today it seems more and more likely that the next great breakthroughs in technology will be brought through a combination of those two sciences with organic chemistry and genetic engineering. This combination is the science of biotechnology.
Organic chemistry enables us to produce marvelous synthetic (合成的) materials. However, it is still difficult to manufacture anything that has the capacity of wool to conserve heat and also to absorb moisture. Nothing that we have been able to produce so far comes anywhere near the combination of strength, lightness and flexibility that we find in the bodies of ordinary insects.
Nevertheless, scientists in the laboratory have already succeeded in "growing" a material that has many of the characteristics of human skin. The next step may well be "biotech hearts and eyes" which can replace diseased organs in human beings. These will not be rejected by the body, as is the case with organs from humans.
The application of biotechnology to energy production seems even more promising. In 1996 the famous science-fiction writer, Arthur C. Clarke, many of whose previous predictions have come true, said that we may soon be able to develop remarkably cheap and renewable sources of energy. Some of these power sources will be biological. Clarke and others have warned us repeatedly that sooner or later we will have to give up our dependence on non-renewable power sources. Coal, oil and gas are indeed convenient. However, using them also means creating dangerously high levels of pollution. It will be impossible to meet the growing demand for energy without increasing that pollution to catastrophic (灾难性的) levels unless we develop power sources that are both cheaper and cleaner.
It is attempting to think that biotechnology or some other "science of the future" can solve our problems. Before we surrender to that temptation we should remember nuclear power. Only a few generations ago it seemed to promise limitless, cheap and safe energy. Today those promises lie buried in a concrete grave in a place called Chernobyl, in the Ukraine. Biotechnology is unlikely, however, to break its promises in quite the same or such a dangerous way.
In 1996, Arthur C. Clarke predicted that

A.biological power sources would be put into use soon.
B.oil, gas and coal could be repeatedly used in the future.
C.dependence on non-renewable power sources would be reduced soon.
D.the Chernobyl disaster would happen in two years.
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单项选择题
According to the last paragraph, which of the following statements is NOT true A.Other cities hope they can also conserve power. B.Other cities hope they can use superconducting cables soon. C.Superconductors waste less power because of their low resistance. D.The Frisbie experiment is not successful.
An underground revolution begins this winter. With the flip (轻击) of a switch, 30,000 homes in one part of Detroit will soon become the first in the country to receive electricity transmitted by ice-cold high-performance cables. Other American cities are expected to follow Detroit’s example in the years ahead, which could conserve enormous amounts of power.
The new electrical cables at the Frisbie power station in Detroit are revolutionary because they are made of superconductors. A superconductor is a material that transmits electricity with little or no resistance. Resistance is the degree to which a substance resists electric current. All common electrical conductors have a certain amount of electrical resistance. They convert at least some of the electrical energy passing through them into waste heat. Superconductors don’t. No one understands how superconductivity works. It just does.
Making superconductors isn’t easy. A superconducting material has to be cooled to an extremely low temperature to lose its resistance. The first superconductors, made more than 50 years ago, had to be cooled to -263 degrees Celsius before they lost their resistance. Newer superconducting materials lose their resistance at -143 degrees Celsius.
The superconductors cable installed at the Frisbie station is made of a ceramic material that contains copper, oxygen, bismuth (铋), strontium (锶) and calcium (钙). A ceramic is a hard, strong compound made from clay or minerals. The superconducting ceramic has been fashioned into a tape that is wrapped lengthwise around a long tube filled with liquid nitrogen. Liquid nitrogen is supercold and lowers the temperature of the ceramic tape to the point where it conveys electricity with zero resistance.
The United States loses an enormous amount of electricity each year to resistance. Because cooled superconductors have no resistance, they waste much less power. Other cities are watching the Frisbie experiment in the hope that they might switch to superconducting cable and conserve power, too.