104. Spending on research and development by LACE w:st="on">United StatesLACE> businesses for 1984 showed an
increase of about 8 percent over the 1983 level. This increase actually continued a downward
trend evident since 1981 – when outlays for research and development increased 16.4 percent
over 1980 spending. Clearly, the 25 percent tax credit enacted by Congress in 1981, which
was intended to promote spending on research and development, did little or nothing to
stimulate such spending.
The conclusion of the argument above cannot be true unless which of the following is true?
(A) Business spending on research and development is usually directly proportional to
business profits.
(B) Business spending for research and development in 1985 could not increase by more
than 8.3%.
(C) Had the 1981 tax credit been set higher than 25%, business spending for research and
development after 1981 would have increased more than it did.
(D) In the absence of the 25% tax credit, business spending for research and development
after 1981 would not have been substantially lower than it was。
这句话怎么翻合适呢？为什么支持题目呢 | 
