Counselor: Those who believe that criticism should be gentle rather than harsh should consider the following: change requires a motive, and criticism that is unpleasant provides a motive. Since harsh criticism is unpleasant, harsh criticism provides a motive. Therefore, only harsh criticism will cause the person criticized to change.
The reasoning in the counselor’s argument is most vulnerable to criticism on the grounds that the argument
(A) infers that something that is
sufficient to provide a motive is necessary to provide a motive - CORRECT.
(B) fails to address the possibility that
in some cases the primary goal of criticism is something other than bringing about change in the person being criticized - WRONG. There might be exceptions that "some" may stand for. Also, primary goal is irrelevant.
(C) takes for granted that
everyone who is motivated to change will change - WRONG. It's not about everyone but in general.
(D) confuses a motive for
doing something with a motive for
avoiding something - WRONG. Altogether irrelevant.
(E) takes the
refutation of an argument to be sufficient to show that the argument’s conclusion is false - WRONG. Where is the refutation?
As per passage
motive leads to change
M ----> Ch
But
uC ----> M
However,
hC = uC
hC ----> M
Therefore, eventually
hC(only) ----> Ch
Further it seems to give an impression that
hC(only) ----> M ----> Ch
Here using "only" suggests that there is no other alternative to "hC", which, in a way, is bit on the extreme side as further assumptions are required to be made. Had "only" not been there, it would still have made sense. This is basically what A says.
Answer A.