GWD7-Q27:

A significant number of complex repair jobs carried out by Ace Repairs have to be reworked under the company’s warranty.  The reworked jobs are invariably satisfactory.  When initial repairs are inadequate, therefore, it is not because the mechanics lack competence; rather, there is clearly a level of focused concentration that complex repairs require that is elicited more reliably by rework jobs than by first-time jobs.

The argument above assumes which of the following?

A.      There is no systematic difference in membership between the group of mechanics who do first-time jobs and the group of those who do rework jobs.

B.       There is no company that successfully competes with Ace Repairs for complex repair jobs.

C.      Ace Repairs’ warranty is good on first-time jobs but does not cover rework jobs.

D.      Ace Repairs does not in any way penalize mechanics who have worked on complex repair jobs that later had to be reworked.

E.       There is no category of repair jobs in which Ace Repairs invariably carries out first-time jobs satisfactorily.

看不懂为什么选A...请求帮助

it is not because the mechanics lack competence和There is no systematic difference in membership between the group of mechanics who do first-time jobs and the group of those who do rework jobs.是一个意思

不是说mechanics 的区别 是说第一次和rework的修复内容不同 第一次是大面积 第二次是focused concentration

我觉得是这样： A:A significant number of complex repair jobs carried out by Ace Repairs have to be reworked under the company’s warranty.  The reworked jobs are invariably satisfactory.

B：When initial repairs are inadequate, therefore, it is not because the mechanics lack competence; rather, there is clearly a level of focused concentration that complex repairs require that is elicited more reliably by rework jobs than by first-time jobs.

要这个A-B的推导成立，就不能削弱A，而选项A满足这个条件。也就是不是能力不行，而是 因为level of focused concentration 的关系导致1，2次结果不同。

也可用排除法。

我做的时候没用排除。理解下题目原意，是rework是必须的，因为侧重点不同。

所以看到A直接就选了。因为第一次和第二次的工人如果不同的话，不能推导出题目的结论：there is clearly a level of focused concentration that complex repairs require that is elicited more reliably by rework jobs than by first-time jobs.