Hello Everyone!

Here is a great example of a question that deals with parallelism!

Whenever we see the idiomatic structure "not only X, but also Y," the first question to ask ourselves is "what do X and Y stand for?" For the idiom to be correct, both X and Y need to be parallel in structure. Let's see how each answer holds up by finding the X and Y:

A. not only undermines one's ability to think critically but also impairs one's overall ability to perceive
This is PARALLEL because both the X and Y parts of the idiom are structured exactly the same, so this is the CORRECT answer!

B. not only undermines one's ability of critical thinking but also impairs the overall ability to perceive
This is NOT PARALLEL because it doesn't repeat the concept of "one's" ability to do things. X is referring to a vague singular person, but Y is referring to everyone in general. Therefore, this is INCORRECT.

C. undermines not only one's ability to think critically but also impairs one's overall ability to perceive
This is NOT PARALLEL because the verb "undermines" is in the wrong place - it should be after "not only." Therefore, this is INCORRECT.

D. undermines not only one's ability of critical thinking but also impairs the overall ability to perceive
This is NOT PARALLEL because the verb "undermines" is in the wrong place, and the phrases "of critical thinking" and "to perceive" aren't parallel. Therefore, this is INCORRECT.

E. undermines one's ability not only to think critically but also impairs one's overall ability to perceive
This is NOT PARALLEL because the phrase "undermine one's ability" needs to come after "not only" for this to be parallel. Therefore, this is INCORRECT.


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