题目内容
几年以前，作为一个减少以橡树叶子为食的吉卜赛蛾数量的方法，昆虫学家在橡树林中引进了一种对吉卜赛蛾有毒的真菌。从此那个地区毛虫和成熟的蛾的数量都显著下降，昆虫学家推论出这些数量的下降归因于有毒真菌的出现。 下面哪一点，如果正确的话，最能支持昆虫学家做出的结论
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Electric Backpack Backpacks are convenient. They can hold your books, your lunch, and a change of clothes leaving your hands free to do other things. Someday, if you don’t mind carrying a heavy load, your backpacks might also power your MP3 player, keep your cell phone running, and maybe even light your way home. Lawrence C. Rome and his colleagues from the University of Pennsylvania in Philadelphia and the Marine Biological Laboratory in WoodsHole, Mass. have invented a backpack that makes electricity from energy produced while its wearer walks. In military actions search-and-rescue operations and scientific field studies, people rely increasingly on cell phones global positioning system (GPS) receivers, night-vision goggles, and other battery powered devices to get around and do their work. The backpack’s electricity-generating feature could dramatically reduce the amount of a wearer’s load now devoted to spare batteries, report Rome and his colleagues in the Sept.9 science. The backpack’s electricity-creating powers depend on springs used to hang a cloth pack from its metal frame. The frame sits against the wearer’s back, and the whole pack moves up and down as the person walks. A gear mechanism converts vertical movements of the pack to rotary motions of an electrical generator, producing up to 7.4 watts. Unexpectedly, tests showed that wearers of the new backpack alter their gaits in response to the pack’s oscillations, so that they carry loads more comfortably and with less effort than they do ordinary backpacks. Because of that surprising advantage, Rome plans to commercialize both electric and non-electric versions of the backpack. The backpack could be especially useful for soldiers, scientists, mountaineers, and emergency workers who typically carry heavy backpacks. For the rest of us, power-generating backpacks could make it possible to walk, play video games, watch TV, and listen to music, all at the same time. Electricity-generating packs aren’t on the market yet, but if you do get one eventually just make sure to look both ways before crossing the street! What is the most important feature of the backpack invented by Lawrence C. Rome and his colleagues
Guessable Future When a magazine for high-school students asked its readers what life would be like in twenty years, they said: Machines would be run by solar power. Buildings would rotate so they could follow the sun to take maximum advantage of its light and heat. Walls would "radiate light" and "change color with the push of a button." Food would be replaced by pills. School would be taught "by electrical impulse while we sleep." Cars would have radar. Does this sound like the year 2000 Actually, (46) and the question was, "what will life be like in 1978" The future is much too important to simply guess about, the way the high school students did, so experts are regularly asked to predict accurately. By carefully studying the present, skilled businessmen, scientists, and politicians are supposedly able to figure out in advance what will happen. But can they One expert on cities wrote: (47) , but would have space for farms and fields. People would travel to work in "airbuses", large all-weather helicopters carrying up to 200 passengers. When a person left the airbus station he could drive a coin-operated car equipped with radar. The radar equipment of cars would make traffic accidents "almost unheard of". Does that sound familiar If the expert had been accurate it would, because he was writing in 1957. His subject was "The city of 1982". If the professionals sometimes sound like high-school students, it’s probably because (48) But economic forecasting, or predicting what the economy will do, had been around for a long time. It should be accurate, and generally it is. But there have been some big mistakes in this field, too. In early 1929, most forecasters saw an excellent future for the stock market. In October of that year, (49) , ruining thousands of investors who had put their faith in financial foreseers. One forecaster knew that predictions about the future would always be subject to significant errors. In 1957, H. J. Rand of the Rand Corporation was asked about the year 2000, "Only one thing is certain," he answered. "Children born today (50) "A. the stock market had its worst losses everB. will have reached the age of 43C. the article was written in 1958D. Cities of the future would not be crowdedE. the prediction of the future is generally accurateF. future study is still a new field
The Case of the Disappearing Fingerprints One useful anti-cancer drug can effectively erase the whorls and other characteristic marks that give people their distinctive fingerprints. Losing (51) become troublesome. A case released online in a letter by Annals of Oncology indicates how big a (52) of losing fingerprints is. Eng-Huat Tan, a Singapore-based medical doctor describes a 62-year old man who has used capecitabine to (53) his nasopharyngeal cancer. After three years on the (54) , the patient decided to visit U.S. relatives last December. But he was stopped by U.S customs officials (55) 4 hours after entering the country when those officials couldn’t get fingerprints from the man. There were no distinctive swirly (56) appearing from his index finger. U.S. customs has been fingerprinting incoming foreign visitors for years, Tan says. Their index fingers are (57) and screened against digital files of the fingerprints of bad guys—terrorists and potential criminals that our federal guardians have been tasked with keeping out of the country. Unfortunately, for the Singapore travelers, one potential (58) effect of his drug treatment is a smoothing of the tissue on the finger pads. (59) , no fingerprints. "It is uncertain when fingerprint loss will (60) to take place in patients who are taking capecitabine," Tan points out. So he cautions any physicians who (61) the drug to provide their patients with a doctor’s note pointing out that their medicine may cause fingerprints to disappear. Eventually, the Singapore traveler made it into the United States. I guess the name on his passport didn’t raise any red flags. But he’s also now got the explanatory doctor’s note-and won’t leave home (62) it. By the way, maybe the Food and Drug Administration, (63) approved use of the drug years ago, should consider (64) its list of side effects associated with this medicine. The current list does note that patients may experience vomiting, stomach pain and some other side effects. But no where (65) it mention the potential for loss of fingerprints.
1988年北美的干旱可能是由太平洋赤道附近温度状况的大面积范围改变时引起的。因此，这场干旱不能证明长期而言全球发生变暖趋势的假说。该趋势据称是由大气污染物如二氧化碳造成的。 下面哪个，如果正确，构成了对以上论述的最好的批判
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