The following questions present a sentence, part of which or all of which is underlined. Beneath the sentence, you will find five ways of phrasing the underlined part. The first of these repeats the original; the other four are different. If you think the original is best, choose the first answer; otherwise choose one of the others.
These questions test correctness and effectiveness of expression. In choosing your answer, follow the requirements of standard written English; that is, pay attention to grammar, choice of words, and sentence construction. Choose the answer that produces the most effective sentence; this answer should be clear and exact, without awkwardness, ambiguity, redundancy, or grammatical error.
The explorers’ chances of surviving the winter, which were good at the beginning of the expedition, dropped as their food supplies dwindled, but not dramatically enough that anyone advocated cannibalism.（）
A. dwindled, but not dramatically enough that anyone advocated
B. have dwindled, but not dramatically enough for anyone to advocate
C. dwindled, but not so dramatically as for anyone to advocate
D. has dwindled, but not dramatically enough that anyone advocated
E. dwindling, but not so dramatically that anyone advocated
参考答案：A
解析：
The verb tense of "dwindled" should correspond to that of "dropped," because these are simultaneous developments; thus, the use of "dwindled" in A and C makes these choices preferable to B, D, and E. The construction "not dramatically enough that" in A is more idiomatic than "not so dramatically as for" in C; A is the best answer.