首页
登录
职称英语
Bracken, a poisonous weed, is spreading and damaging much pastureland in the Nor
Bracken, a poisonous weed, is spreading and damaging much pastureland in the Nor
游客
2025-02-26
13
管理
问题
Bracken, a poisonous weed, is spreading and damaging much pastureland in the Northern Hemisphere. One potentially inexpensive and self-sustaining countermeasure is to introduce natural enemies of the plant; therefore, some scientists have proposed to control bracken by a release of bracken-eating moths native to the Southern Hemisphere into bracken-infested areas in the Northern Hemisphere. If the scientists’ proposal for controlling bracken is adopted, which of the following is a necessary condition for its success?
选项
A、That bracken in the Northern Hemisphere grows in approximately the same climates and soil conditions in which it grows in the Southern Hemisphere.
B、That the released moths will feed on weeds other than bracken that are native to the Northern Hemisphere.
C、That the livestock that will return to pastures now lost to bracken will develop immunities to the diseases caused by bracken.
D、That the released moths will survive in sufficient numbers to build a population large enough to reduce bracken and retard its growth.
E、That traditional methods of control, such as burning, cutting, and chemical spraying, will not become less expensive or labor-intensive than they are now.
答案
D
解析
转载请注明原文地址:http://tihaiku.com/zcyy/3973297.html
相关试题推荐
Bracken,apoisonousweed,isspreadinganddamagingmuchpasturelandintheNor
BUMPER:DAMAGING::A、ballast:founderingB、scale:comparingC、buoy:navigatingD、dr
BUMPER:DAMAGING::A、ballast:founderingB、scale:comparingC、buoy:navigating
Unfortunately,hisdamagingattacksontheramificationsoftheeconomicpolicy
随机试题
[originaltext]Althoughpeopleoftenusethephrase"thedictionary",there
Whydidn’tpeoplebegintouseunmannedvehiclesinunderseaexplorationuntilr
【B1】[br]【B3】[audioFiles]audio_eusm_j01_273(20099)[/audioFiles]childbearing40前
TheInternetisa【B1】______networkofcomputers【B2】______allovertheworld
A.约束纵行躯干的诸条经脉 B.调节六阴经经气 C.调节肢体运动 D.调节
下图作品的作者为()。 A.周文矩 B.吴道子 C.阎立本 D.顾
患者,女,33岁,护士为她作了妇科检查后,又指导一男实习生做了一遍。此举引起了患
心理诊断的目标与一般性心理学研究的目标是极不相同的。一般心理学研究的目标是寻求(
在面试过程中,考官应当表现出的行为是()。A:制造紧张情绪,使求职者无法表现出真
参加竣工验收监测采样和测试的人员,按国家有关规定持证上岗;监测仪器在检定有效期内
最新回复
(
0
)