首页
登录
职称英语
What conclusion can be drawn from the scientists’ observation? [br] [originalte
What conclusion can be drawn from the scientists’ observation? [br] [originalte
游客
2023-11-06
10
管理
问题
What conclusion can be drawn from the scientists’ observation? [br]
Scientists have discovered that plants themselves pro-duce many poisonous chemicals for defense against insects. But insects have developed ways of dealing with them and, in fact, have been eating plants for about 250 million years. Now insects are using these same mechanisms to deal with man-made poisons--insecticides. This is why resistance of insects to insecticides has developed so rapidly.
What should be done? Scientists studying the problem suggest that farmers use less insecticides. At the moment, farmers regularly spray crops as a precaution against problems that are caused by large numbers of pests. They should, instead, spray only where pests have actually been seen. Secondly, farmers could use a combination of two or three insecticides at once. To survive, the insects would need to become resistant to two or more insecticides at the same time.
The most surprising suggestion, perhaps, is that at certain times of the year, farmers should actually try to at-tract insects onto the crops they are trying to protect. The new insects will mate with those which survived from a certain kind of insecticide and will lessen the latter’s resistance to it.
Scientist hope that these and other measures will post-pone the day when farmers and scientists will have to stand by while new super-bugs which may be resistant to all poi-sons invade our farms and devour our crops.
选项
A、Farmers should use less insecticides.
B、Farmers should use a combination of two or three insecticides at once.
C、At certain times of the year, farmers should actually try to attract new insects onto the crops they are trying to protect.
D、Farmers should regularly spray crops as a precaution against problems that are caused by large numbers of pests.
答案
D
解析
“They should,instead,spray only where pests have actually been seen.”,“Secondly,farmers could use a combination of two or three insecticides at once.”,“farmers should actually try to attract insects onto the crops they are trying to protect”选项A,B,C在课文中都有提
转载请注明原文地址:https://tihaiku.com/zcyy/3163683.html
相关试题推荐
PresidentObamaplanto[br][originaltext]OfficialsinWashingtonsayPres
PresidentObamaplanto[originaltext]OfficialsinWashingtonsayPresident
Whatisthenewsitemmainlyabout?[originaltext]Theamountofproductstha
Wherecanpeopletakeadulteducationcourses?[br][originaltext]Millions
Wherecanpeopletakeadulteducationcourses?[br][originaltext]Millions
Whatisthepassagemainlyconcernedabout?[br][originaltext]Sleepisv
Whatisthepassagemainlyconcernedabout?[br][originaltext]Sleepisv
Whatisthepassagemainlyconcernedabout?[originaltext]Sleepisveryan
Modernholistictreatmentfocuseson______.[br][originaltext]Theoldestf
Modernholistictreatmentfocuseson______.[br][originaltext]Theoldestf
随机试题
Asfansenjoyfootball’s(soccer’s)month-longWorldCup,Brazilianauthoritie
Twostudentsaremajoringinpsychology.Inthefollowingtheyarediscussingab
Small______theroomis,itispleasantandairy.A、whoB、asC、thatD、likeB空格前的
Personalityistoalargeextentinherent—Atypeparentsusuallybringabout
共用题干 某男性患者,40岁。有精神分裂症病史10年,近两月服用大剂量氯氮平治
“国际评估准则102——调查和遵循”主要规定了评估实施过程中应注意的相关问题,包
甲企业2017年的赊销净额为850000元,期初应收账款余额为240000元,期
某投资者以8000万元购买一栋写字楼用于出租经营,其中的40%为银行提供的抵押贷
原核生物复制中辨认起始点的蛋白质是( )。A.DnaA B.DnaB C.
某会员在4月1日开仓买入大豆期货合约,交易保证金比例为5%。该会员上一交易日结算
最新回复
(
0
)