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.
At the MegaTek Corporation, an inexperienced financial analyst mistook the rising cost of semiconductors as a seasonal fluctuation in the market.（）
A. the rising cost of semiconductors as a seasonal fluctuation
B. rise in price of semiconductors as a seasonal fluctuation
C. rising cost of semiconductors for a seasonal fluctuation
D. rising of the cost of semiconductors for a fluctuation by season
E. rise of semiconductors in price to a seasonal fluctuation