"Junk science" is how Elliot Morley, Britain’s minister responsible for genetically modified farming, describes studies that cla

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问题     "Junk science" is how Elliot Morley, Britain’s minister responsible for genetically modified farming, describes studies that claim GM crops would be hazardous to Britain’s wildlife and consumers. This week the government granted permission for a strain of GM maize to be grown commercially as cattle feed. That has incensed environmentalists and organic farmers, who say GM is unpopular(probably correct)and based on bad science(probably not).
    Three years of field testing have shown the herbicide-resistant maize, Bayer’s Chardon LL, to be safe and even kinder to the environment than non-GM maize. Two other crops on trial—a GM sugar-beet and a GM oilseed rape—will not be grown because they were worse for biodiversity(weeds)than conventional strains.
    The trials have not made the worries about introducing even a safe GM crop go away, though. Opponents say GM will stealthily take over the country by cross-pollination, will damage wildlife and introduce something nasty into the human food chain. How solid is all this?
    Evidence from America, which planted 105. 7m acres of biotech crops in 2003, suggests concerns are overblown. In practice it is easy to separate crops and prevent them from cross-pollinating. Even oilseed rape, which is particularly promiscuous, can be kept over 99% pure if it is a hundred metres away from another plantation. Cross-pollination probably will happen, but so far it has caused no problems: genetic material in plants changes all the time through sexual reproduction anyway.
    Damage to wildlife is difficult to measure, but there is evidence that GM has had a positive effect, with birds and insects returning to GM cotton plantations in America. Certainly, GM crops tend to need fewer chemicals to protect them. Monsanto says its sugarbeet, which was on trial along with the Chardon maize, requires 46% less herbicide than a conventional strain. Supposed threats to consumers, whether human or animal, are the most flaky. One recent study appeared to show that Chardon maize could be fatal to cattle, but the heifer in question in fact died from botulism. The British Medical Association now says there is "very little potential for GM foods to cause harmful health effects" in people either. People have been eating the stuff in America for years, with no ill effects so far.
    The messing around with genetic material that makes some people dislike GM crops has gone on for years in conventional plant breeding, where crops are exposed to radiation and chemicals to encourage them to mutate. According to the International Atomic Energy Agency in Vienna, over 2, 000 types of crop have been bombarded with gamma rays to produce mutants, many of which are grown by organic farmers.
    " All food is frankenfood, " according to Professor Howard Dalton, chief scientific adviser to the Department for Food and Rural Affairs, "but everybody’s got used to it. " Maybe everybody will get used to GM soon, too.
Field testing in America has shown that

选项 A、non-GM crops are more environment-friendly than GM crops.
B、concerns over the threats of GM crops are exaggerated.
C、GM crops pose serious threats to biodiversity.
D、cross-pollination has introduced nasty species into the human food chain.

答案B

解析 细节题。题目问的是“美国的田间测试说明了什么?”。由第二段可知,已经有实验证明了存在环境友好型的转基因作物,当然也存在对生物多样性有影响的转基因作物,A、C项太绝对了,故排除。转基因反对者认为,转基因会引入一些不好的东西,这不是田间测试的内容,故排除D项。由第四段第一句“Evidence fromAmerica,which planted 105.7m acres of biotech crops in 2003,sug—gests concerns are overblown.”可知人们的担忧有些多虑了,故选B。
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