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In the forests of New Brunswick, for example, various pesticides have been sprayed in the past 25 years in efforts to control the spruce budworm, an economically significant pest. Scientists have now investigated the effects of the spraying of Matacil, one of the anti-budworm agents that is least toxic to insect-pollinators. They studied Matacil’s effects on insect mortality in a wide variety of wild insect species and on plant fecundity, expressed as the percentage of the total flowers on an individual plant that actually developed fruit and bore seeds. They found that the most pronounced mortality after the spraying of Matacil occurred among the smaller bees and one family of flies, insects that were all important pollinators of numerous species of plants growing beneath the tree canopy of forests. The fecundity of plants in one common indigenous species, the red-osier dogwood, was significantly reduced in the sprayed areas as compared to that of plants in control plots where Matacil was not sprayed. This species is highly dependent on the insect-pollinators most vulnerable to Matacil. The creeping dogwood, a species similar to the red-osier dogwood, but which is pollinated by large bees, such as bumblebees, showed no significant decline in fecundity. Since large bees are not affected by the spraying of Matacil, these results add weight to the argument that spraying where the pollinators are sensitive to the pesticide used decreases plant fecundity.



4.
The passage suggests that which of the following is true of the forest regions in New Brunswick sprayed with most anti-budworm pesticides other than Matacil?



(A) The fecundity of some flowering plants in those regions may have decreased to an even greater degree than in the regions where Matacil is used.

(B) Insect mortality in those regions occurs mostly among the larger species of insects, such as bumblebees.

(C) The number of seeds produced by common plant species in those regions is probably comparable to the number produced where Matacil is sprayed.

(D) Many more plant species have become extinct in those regions than in the regions where Matacil is used.


(E) The spruce budworm is under better control in those regions than in the regions where Matacil is sprayed.

A答案,但是E为什么不对,是文章讨论对象的问题?

望解答,谢谢^_^

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文章没有说道杀虫剂那个对这个虫子更有效。

文章通篇都是说对于传播花粉的昆虫那种杀虫剂影响更大。

因此E中不知道mataci还是其他杀虫剂对budworm更厉害。

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文章说了matacil是[size=+0]
    least toxic,所以才能得到A的。。。
我是不知道既然least toxic可以得到A,那么least toxic也应该得到E
因为逻辑上pesticide导致 虫子少 导致 传粉受影响 ,即E应该是A的必要条件
那么为什么A对了,E就不对呢?

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least toxic to insect-pollinators
budworm怎么会是pollinators

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