A transit company’s bus drivers are evaluated by supervisors riding wi

Why C is wrong?

conclusion: Driver will likely to be perform best in normal condition, IF driver performance is BEST with a supervisor aboard.

C is a defender assumption.
on the other hand D: talking abt "extent " ,each driver affeted with!

Hello Experts,

Option C is incorrect because it talks about most bus drivers while the conclusion talks only about bus drivers who perform best with supervisors.
Is that why we should reject C?

If the answer choice stated " For some drivers who performed best with supervisors, their performance would be slightly worse than it was without supervisors"

Would it be a correct assumption then?

For answer choice D, i think focus of the conclusion is also on 'being the best drivers'.. To be best, they all have to be equal performers , not more not less, they can not be better than each other to be best...They all have to be best (equally best performers)

and that's what choice D attacks, if they are not equally good/equally impacted then they can not all be the best drivers under normal conditions.

Is my understanding correct?

A transit company’s bus drivers are evaluated by supervisors riding with each driver. Drivers complain that this affects their performance, but because the supervisor’s presence affects every driver’s performance, those drivers performing best with a supervisor aboard will likely also be the best drivers under normal conditions.

Core- because the supervisor’s presence affects every driver’s performance, those drivers performing best with a supervisor aboard will likely also be the best drivers under normal conditions.
Type- assumption
Pre-thinking- does the presence of a supervisor affect the performance of all drivers to the same degree?

(A) There is no effective way of evaluating the bus drivers’ performance without having supervisors ride with them.- incorrect
(B) The supervisors are excellent judges of a bus driver’s performance.- irrelevant; the efficacy of this process is not relevant
(C) For most bus drivers, the presence of a supervisor makes their performance slightly worse than it otherwise would be.- incorrect; 'most' is an issue here; we know that some drivers are NOT negatively affected by the presence of supervisors. If the worst drivers were not affected negatively, then our results will be misleading
(D) The bus drivers are each affected in roughly the same way and to the same extent by the presence of the supervisor.- Correct
(E) The bus drivers themselves are able to deliver accurate assessments of their driving performance.- incorrect

Answer D

Skywalker18

if i consider that the supervisor is not an excellent judge,ie., can be somehwhat inaccurate or biased , wont that affect the conclusion?? Coz we are given hta supervisors evalutae the perfomance !! wat if they are inaccurate in judging the best normal deivers or are biased??

On the other hand, D is also a fair assumption. The reason i selected D is that we are given that "drivers are affected by S presence" . so the assumtion should have been around this.

Please elaborate more on why option B is incorrect !!!

Hi AdityaHongunti,

1. Firstly, the efficacy of supervisors is not relevant to the conclusion - drivers performing best with a supervisor aboard will likely also be the best drivers under normal conditions.
None of the statements imply that the supervisors are excellent in supervising.
Also, the negation of option B is 'The supervisors are NOT excellent judges of a bus driver’s performance'
The negation has no effect on the strength of the author’s conclusion—the presence of a supervisor should not adversely affect the determination of the best drivers.

2. If we change the conclusion to - "Those drivers rated best by a supervisor aboard will likely also be the best drivers under normal conditions." -- in this case, we are taking into consideration the efficacy of the supervisor's review.
But even this argument(with the updated conclusion) seems to be correct even if the supervisors are good(okayish but not excellent) judges of a bus driver’s performance.

Hope this helps!!

PowerScore Complete Question Explanation

Assumption. The correct answer choice is (D)

When a transit company sends supervisors to evaluate its bus drivers, the drivers complain that
the supervisor’s presence affects their performance. The author of the stimulus, however, argues
that since all drivers are affected by the presence of a supervisor, those who perform best with a
supervisor aboard will probably be the best performers under normal circumstances as well.

The stimulus is followed by an Assumption question, so the correct answer choice will provide an
assumption upon which the author’s argument depends.

The author appears to assume that since all of the drivers have to deal with the same experience, that
the supervisor’s presence would have the same effect on everyone. The problem, of course, is that
not everyone would necessarily respond to the supervisor’s presence in the same way—some might
be more cautious than normal, driving better because of an awareness of being monitored, while
others might be affected negatively by someone looking over their shoulder, watching their every
move.

Answer choice (A): The author does not assert or even suggest that the direct supervision is the only
effective way of monitoring bus drivers. Rather, the author simply advances the argument that such
supervision should not skew the results when determining the best drivers. To confirm this choice
to be incorrect, we can apply the Assumption Negation technique, by negating the statement and
assessing its effects on the author’s argument—the negated version of the correct answer choice
(Direct supervision is not the only way to monitor bus drivers) does not hurt the author’s argument at
all, so this choice can be eliminated.

Answer choice (B): The author’s comments deal with the issue of whether or not the presence of a
supervisor will throw off the results in determining the best drivers. There is no discussion of how
good a job the supervisors might do, and none of the author’s statements suggest or imply that the
supervisors are “excellent” at supervising.

To confirm that this answer choice should be eliminated, we can apply the Assumption Negation
technique: again, the negated version of the correct answer choice should weaken the author’s
conclusion. The supervisors are not excellent judges of a bus driver’s performance. This negated
version has no effect on the strength of the author’s conclusion—that the presence of a supervisor
should not throw off the determination of the best drivers.

Answer choice (C): The author assumes that the effects of the supervisor will be the same for all
of the drivers but does not specify what type of effect that might be—positive or negative, great or
slight.

Answer choice (D): This is the correct answer choice. If the author believes that the best
supervised drivers will also be the best unsupervised, the assumption is that the effect of being
supervised will be roughly the same for everyone.

Answer choice (E): Although the stimulus provides that the drivers complain about the presence of
supervisors, no one presents or alludes to the idea that the drivers could effectively assess their own
driving performance.

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