首页
登录
职称英语
[originaltext] (32)Scientists have discovered that plants themselves produce
[originaltext] (32)Scientists have discovered that plants themselves produce
游客
2023-09-09
50
管理
问题
(32)Scientists have discovered that plants themselves produce many poisonous chemicals for defense against insects. But insects have developed ways of dealing with them. Guess how many years have the insects been eating plants. The number itself will scare you. (33) In fact, insects have been eating plants for as many as 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 (34) that farmers use less insecticides. At the moment, farmers (34)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, (34)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 attract new 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.
(35) Scientists hope that these and other measures will postpone the day when farmers and scientists will have to stand by while new super-bugs which may be resistant to all poisons invade our farms and devour our crops.
选项
A、Farmers should use less insecticide:
B、Farmers should use a combination of two or three insecticides at once.
C、Farmers should attract new insects onto the crops certain times.
D、Farmers should regularly spray crops as a precaution.
答案
C
解析
本题选项中A、B、D均可在文中第二段找到相应话语。故正确答案为C。
转载请注明原文地址:http://tihaiku.com/zcyy/2999549.html
相关试题推荐
[originaltext]Anewreportsaysthecostofstudiesatpubliccollegesint
[originaltext]Today,airtravelisfarsaferthandrivingacaronabusym
[originaltext]Today,airtravelisfarsaferthandrivingacaronabusym
[originaltext]Motivationcancomefromthreesources,twoofthemexternal
[originaltext]M:Hi,Diana.MindifIsitdown?W:Notatall,Jack.Howhavey
[originaltext]M:Hi,Diana.MindifIsitdown?W:Notatall,Jack.Howhavey
[originaltext]W:Goodevening,professorMynameisAliceBrown.M:Goodevenin
[originaltext]W:Goodevening,professorMynameisAliceBrown.M:Goodevenin
[originaltext]W:Whydidn’tyougotothehockeyfinalslastweekend?Youmisse
[originaltext]W:Whydidn’tyougotothehockeyfinalslastweekend?Youmisse
随机试题
•Youwillhearanotherfiveshortpieces.•Eachspeakeristalkingabouttheeff
TheoriesofHistoryI.Howmuchweknowabouthistory?
【B1】[br]【B4】A、decisionsB、tasksC、worksD、responsibilitiesA
关于数字内容资源的审核,说法正确的有( )。A.内容资源审核必须全部由人工完成
A.孢子含有脂肪油,海金沙素等B.主要含有左旋龙脑,尚含异龙脑C.采收加工是在冬
下面一段是心理咨询师与求助者访谈片段,请据此回答问题。 心理咨询师:你遇到什么
共用题干 一般资料:求助者,女性,27岁,公司职员。案例介绍:求助者不合群,经
长期债券一般没有()发行方式。A.平价 B.折价 C.溢价 D.等价
新增流动资产中的应收及预付款项包括()A.银行存款 B.预付货款 C
双胍类降糖药易出现的不良反应是A.严重腹泻 B.酮症酸中毒 C.乳酸血症
最新回复
(
0
)