OFFICIAL KAPLAN EXPLANATION
Step 1: Identify the Question Type
This is a Weaken question, as it asks for a choice that goes against making relocation permanent.
Step 2: Untangle the Stimulus
The bank took some bankers and had them try out the commute for three months. During that time, these bankers' sales were higher than those of their colleagues who did not commute. The bank, if it uses this trial period to support the decision to move the office permanently, is assuming that the commute was what caused the higher sales.
Step 3: Predict the Answer
The correct choice will attack the bank's assumption. It will suggest something else as the cause of the higher sales achieved by the volunteers who commuted.
Step 4: Evaluate the Choices
(A) suggests some other reason for the higher sales, besides the commute. The volunteers were loyal and “hardest-working,” and therefore might be expected to achieve higher sales no matter where they are. Thus, the bank shouldn't expect the same results from the other bankers, and it wouldn’t be a good idea to make the move permanent just based on this small trial. (A) is therefore correct.
(B) actually supports the idea of a permanent move, but really is irrelevant to the argument in the stimulus because it doesn't deal with the trial period in question. The argument is that the move is supported by the findings of the trial period. (B) doesn’t address that.
(C) is irrelevant, as the argument is about the connection between the findings of the trial period and the decision to make the move permanent. The experiences of competitor banks have nothing to do with this connection.
(D) just explains how the employees in the trial were able to continue doing their banking work. This doesn't make the permanent location of the main office seem like a bad idea at all.
(E) brings up the possibility of other methods to raise sales. This is irrelevant to the question of whether the results of the trial period demonstrate that the commute itself was responsible for the high sales observed.
TAKEAWAY: With Weaken questions, keep the focus on the connection between the stated evidence and the conclusion - the assumption. Don't forget that the task is to attack that connection. That will make it easier to avoid wrong choices.