首页
登录
职称英语
In Asia, where palm trees are non-native, the trees’ flowers have traditionally
In Asia, where palm trees are non-native, the trees’ flowers have traditionally
游客
2024-01-13
40
管理
问题
In Asia, where palm trees are non-native, the trees’ flowers have traditionally been pollinated by hand, which has kept palm fruit productivity unnaturally low. When weevils known to be efficient pollinators of palm flowers were introduced into Asia in 1980, palm fruit productivity increased— by up to fifty percent in some areas—but then decreased sharply in 1984 . Which of the following statements, if true, would best explain the 1984 decrease in productivity?
选项
A、Prices for palm fruit fell between 1980 and 1984 following the rise in production and a concurrent fall in demand.
B、Imported trees are often more productive than native trees because the imported ones have left behind their pests and diseases in their native lands.
C、Rapid increases in productivity tend to deplete trees of nutrients needed for the development of the fruit-producing female flowers.
D、The weevil population in Asia remained at approximately the same level between 1980 and 1984.
E、Prior to 1980 another species of insect pollinated the Asian palm trees, but not as efficiently as the species of weevil that was introduced in 1980.
答案
C
解析
如果(C)是正确的,1980年后亚洲棕榈树产量的迅速提高耗尽了培育果实的雌花生长需要的营养物质,因此(C)解释了为什么棕榈的产量随后下降,即(C)为正确答案;选项(A)将棕榈果实价格的下降与产量的增加和需求的下降联系起来,但没有解释随后该树产量的下降;选项(B)没有给出这些引入亚洲的树产量下降的原因;(D)也没有,因为(D)中描述的象鼻虫数量的稳定应支持在1980年到1984年之间棕榈树果实产量的稳定,而不是下降;因为(E)描述了1980年以前该树的授粉情况,它没有解释发生在1984年的变化
转载请注明原文地址:https://tihaiku.com/zcyy/3358456.html
相关试题推荐
Withtheflowers______everywhere,theparklooksbeautiful.A、tobloomB、blooming
Traditionally,universitieshavecarriedouttwomainactivities:researcha
Traditionally,universitieshavecarriedouttwomainactivities:researcha
Traditionally,universitieshavecarriedouttwomainactivities:researcha
ThesewildflowersaresospecialthatIwoulddo________Icantosavethem.A、wh
Traditionally,universitieshavecarriedouttwomainactivities;researcha
Traditionally,universitieshavecarriedouttwomainactivities;researcha
Theseplasticflowerslookso______thatmanypeoplethinktheyarereal.A、beaut
Textbookpricesaretraditionallyhigh."Combinedwiththerisingcostoft
Textbookpricesaretraditionallyhigh."Combinedwiththerisingcostoft
随机试题
Atatimewhenitwasunusualtodoit,DorothySterlingwroteaboutsuchmajor
设f1(x),f2(x)是二阶线性齐次方程y″+p(x)y′+q(x)y=0的两
与锤造支托相比较,铸造支托突出的优点是()A.恢复咬合关系和良好的牙
金融犯罪的主体是()。A.只能是自然人 B.金融企业 C.可以是自然
某客户3月15日通过电话委托购买了一只开放式基金,委托金额为20000元,该只基
建设单位应当将大型的人员密集场所和其他特殊建筑工程的消防设计文件报送公安机关消防
期货公司的期货从业人员不得有下列()行为。A:收付、存取或者划转期货保证金
流动动物园巡回展出用羊
农业生产托管情况统计中,农业生产托管服务面积核算中“耕”环节面积的权重是(
2010年全国财政收入为83080亿元,其中中央财政收入为42470亿元,当年全
最新回复
(
0
)