An overwhelming proportion of the most productive employees at SaleCo’s regional offices work not eight hours a day, five days a week, as do other SaleCo employees, but rather ten hours a day, four days a week, with Friday off. Noting this phenomenon, SaleCo’s president plans to increase overall productivity by keeping the offices closed on Fridays and having all employees work the same schedule—ten hours a day, four days a week.

Which of the following, if true, provides the most reason to doubt that the president’s plan, if implemented, will achieve its stated purpose?

A. Typically, a SaleCo employee’s least productive hours in the workplace are the early afternoon hours.

B. None of the employees who work four days a week had volunteered to work that schedule, but all were assigned to it by their supervisors.

C. Working ten hours a day has allowed the most productive employees to work two hours alone each day in their respective offices relatively undisturbed by fellow employees.

D. Employees at SaleCo are compensated not on the basis of how many hours a week they work but on the basis of how productive they are during the hours they are at work.

E. Those SaleCo employees who have a four-day workweek do not take any of their office work to do at home on Fridays.

答案是C, C是什么意思呢，怎么能构成削弱呢？多谢大师指点！

如果选b应该是没有“工作五天的人”同意工作四天，不是没有"工作四天的人".因为改变的是一般员工的时间，不是有效率的员工的时间。

我做这道题是把选项全看了一遍才选出来的，因为abde明显不对,abde都排除了才选了c。

我想c的意思就是说由于工作安排得改变，使得那些最有生产力的雇员可以在他们的单间办公室里每天只工作两个小时，（我们不要管为什么工作安排得改变有这种效果，只要他这么说就这么认为）。题目本来是想通过实行新的安排increase overall productivity，可是这种新的安排虽然减少了星期五办公室成本的耗费却使最有效率的员工工作效率降低，当然削弱了题目。