Plant scientists have used genetic engineering on seedsto produce crop plants that are highly resistant to insect damage. Unfortunately,the seeds themselves are quite expensive, and the plants require morefertilizer and water to grow well than normal ones. Thus, for most farmers the savings on pesticideswould not compensate for the higher seed costs and the cost of additionalfertilizer. However, since consumer demand for grains, fruits, and vegetables grownwithout the use of pesticides continues to rise, the use of geneticallyengineered seeds of this kind is likely to become widespread.
In the argument given, the two portions in boldface play which of the followingroles?
(A) The first supplies a context for the argument; thesecond is the argument's main conclusion.
(B) The first introduces a development that the argumentpredicts will have a certain outcome; the second is a state of affairs that theargument denies will be part of that outcome.
(C) The first presents a development that the argumentpredicts will have a certain outcome; the second acknowledges a considerationthat weighs against that prediction.
(D) The first provides evidence to support a predictionthat the argument seeks to defend; the second is that prediction.
(E) The first and the second each provide evidence tosupport the argument's main conclusion.
参考答案: C
思路：However后面与作者立场一致, However前面与作者立场相反。
A：排除;因为The frist应该与argument立场相反
B：排除，因为the second is a state of affairs that the argument denies错了. The second应该与argument的立场一致.
D：排除，因为The first应该与作者立场相反;
E：排除，因为The first应该与作者立场相反;
C：第一句话是argument预测的一个结果. 预测就有可能支持或反对; 第二句话反对了预测的东西,也就是反对一句话。没有什么错, 不能排除.