材料：The Official SAT Study Guide
试卷：3
页数：576
题号：42
Questions 42-52 are based on the following passage and supplementary material.
This passage is adapted from Richard J. Sharpe and Lisa Heyden, “Honey Bee Colony Collapse Disorder is Possibly Caused by a Dietary Pyrethrum Deficiency.” ©2009 by Elsevier Ltd. Colony collapse disorder is characterized by the disappearance of adult worker bees from hives.
We suspect that the bees of commercial bee colonies which are fed mono-crops are nutritionally deficient. In particular, we postulate that the problem is a diet deficient in anti-mite toxins: pyrethrums, and possibly other nutrients which are inherent in such plants. Without, at least, intermittent feeding on the pyrethrum producing plants, bee colonies are susceptible to mite infestations which can become fatal either directly or due to a secondary infection of immunocompromised or nutritionally deficient bees. This secondary infection can be viral, bacterial or fungal and may be due to one or more pathogens. In addition, immunocompromised or nutritionally eficient bees may be further weakened when commercially produced insecticides are introduced into their hives by bee keepers in an effort to fight mite infestation. We further postulate that the proper dosage necessary to prevent mite infestation may be better left to the bees, who may seek out or avoid pyrethrum containing plants depending on the amount necessary to defend against mites and the amount already consumed by the bees, which in higher doses could be potentially toxic to them.
42. How do the words “can,” “may,” and “could” in the third paragraph (lines 19-41) help establish the tone of the paragraph?
A) They create an optimistic tone that makes clear the authors are hopeful about the effects of their research on colony collapse disorder.
B) They create a dubious tone that makes clear the authors do not have confidence in the usefulness of the research described.
C) They create a tentative tone that makes clear the authors suspect but do not know that their hypothesis is correct.
D) They create a critical tone that makes clear the authors are skeptical of claims that pyrethrums are inherent in mono-crops.
答案: C
答案解析: 本题问第三段中的 “can,” “may,” and “could” 是如何辅助建立文章的语气基调的。首先分析 “can,” “may,” “could” 这三个词，它们同属于情态动词，会有含义上的差别，但这三个词都能表示的含义是 “可能”，带有不确定的语气。同时，文章提到 “We suspect that…”(Line 19) 以及 “We further postulate that” (Line 35)，也印证了这是由 “假设、猜测” 产生的不确定性。
A选项中的 “optimistic tone” 显然与这三个词的语气基调不符，可以快速排除。
B选项说是“怀疑”的语气，因为作者对研究的实用性不自信。文章描述了作者的假设，但是没有任何依据体现出作者对其实用性产生了怀疑，因此排除。
C选项说是 “假设” 的语气，因为作者不确定自己的猜想是否正确，符合上述分析，因此该选项为最佳答案。
D选项中的 “critical tone” 与这三个词的语气基调也不符，因此排除。
重点词汇：
suspect: [səˈspekt] v. 怀疑;猜想
deficient: [dɪ'fɪʃ(ə)nt] adj. 不足的;有缺陷的;不充分的
postulate: ['pɒstjʊleɪt] vt. 假定;要求;视…为理所当然 | n. 基本条件;假定
toxin: ['tɒksɪn] n. 毒素;毒质
pyrethrum: [paɪ'riːθrəm] n. 除虫菊杀虫剂
nutrient: ['njuːtrɪənt] n. 营养物;滋养物 | adj. 营养的;滋养的
inherent: [ɪn'hɪər(ə)nt] adj. 固有的;内在的;与生俱来的，遗传的
infestation: [,ɪnfe'steɪʃən] n. 感染;侵扰
compatible: [kəm'pætɪb(ə)l] adj. 兼容的;能共处的;可并立的
immunocompromised: [,ɪmjəno'kɑmprəmaɪzd] adj. 免疫功能不全的
pathogen: ['pæθədʒ(ə)n] n. 病原体;病菌
insecticide: [ɪn'sektɪsaɪd] n. 杀虫剂