首页
登录
职称英语
Over the last 40 years there has been a great increase not only in the number of
Over the last 40 years there has been a great increase not only in the number of
游客
2024-01-13
58
管理
问题
Over the last 40 years there has been a great increase not only in the number of agricultural pesticides in use but also in the care and sophistication with which they are used by farmers. Nevertheless, the proportion of agricultural crops lost to certain pests worldwide has increased over the same period, even when the pests concerned have not developed resistance to existing pesticides. Which of the following, if true, best explains how improvements in pesticide use have been accompanied by greater losses to certain pests?
选项
A、Some dangerous but relatively ineffective pesticides common 40 years ago are no longer in widespread use.
B、As pesticides have become increasingly pest-specific, controlling certain pests with pesticides has turned out to cost more in many cases than the value of crop losses caused by those pests.
C、Because today’s pesticides typically have more specific application conditions than did pesticides in use 40 years ago, today’ s farmers observe their fields more closely than did farmers 40 years ago.
D、Certain pest-control methods that some farmers use today do not involve the use of chemical pesticides but are just as effective in eliminating insect pests as those that do.
E、Eorty years ago, much less was known about the effects of pesticides on humans and other mammalian species than is now known.
答案
B
解析
本题为解释题型,让我们寻求一个选项去解释为什么杀虫剂使用方面的改进伴随某些害虫的损失却更大。(B)说明由于单个针对性增强,导致用杀虫剂控制某种害虫的成本变得比那种害虫带来的损失的价值更大,与我们要解释的相吻合,起到了解释作用,因此(B)正确;(A)选项起到部分反对作用;(C)只是解释了农民为什么更仔细;(D)说的是共同点,无法解释上面的似乎不合常理的说法;(E)为新比较,且了解程度与损失等无关
转载请注明原文地址:https://tihaiku.com/zcyy/3358927.html
相关试题推荐
Duringthelastthreedecades,thenumberofpeopleparticipatinginphysicalfi
Oursloganis"Quantityshouldneverbeincreasedatthe______ofquality".A、pr
VisitorsfromtheUShaveincreased______8percentsincelastyear.A、byB、inC、w
Thenumberofcollegegraduatesgoingintobusiness-relatedfieldshas______incr
Thegrowthofachildisinfluencedbyanumberoffactors,______arebeyondour
TheAmericanandtheBritish______alargenumberofsocialcustoms.A、joinB、tak
Thefactoryhadto______anumberofemployeesbecauseoftheeconomicdeclinein
Thenumberofprimaryschoolsintheruralareas______doublinginthepast50ye
Toimprovethe______isregardedasagoodmethodtoincreasethefarmer’sincom
Normallyastudentmustattendanumberofcoursesinordertograduate,and
随机试题
InsurveysMasonCityresidentsrankwatersports(swimming,boating,andfishing
Readinginvolveslookingatgraphicsymbolsandformulatingmentallythesounds
HowtoSucceedinYourLiteratureClassI.Featuresofliteratureclass—extre
"Home,sweethome"isaphrasethatexpressesallessentialattitudeinthe
对行业不同时期资本进退的情况描述正确的有() Ⅰ.成熟期之前,企业数量
下列药物中,肾功能不良的患者绿脓杆菌感染时可选用的是A.氨苄西林B.克林霉素C.
被乙肝患者血液污染的医疗用品,正确的消毒方法是A.用含有效氯100mg/L的含氯
晋:粤A.豫:闽 B.冀:滨 C.黔:川 D.湘:桂
局麻时如麻醉药不慎注入腮腺,则会引起( )。A.感染 B.血肿 C.牙关紧
唾液腺造影的禁忌证是A:肿瘤 B:慢性炎症 C:涎瘘 D:急性化脓性腮腺炎
最新回复
(
0
)