GMAT Sentence Correction (SC) | Re: SC - use of idioms example

Whenever there is a not only but also idiom, we can look at both sides of that idiom and make sure they match, that they are parallel.

If there's a verb one side, like using, there should be a verb on the other side, if there's a noun on one side, like reduction, there should be a noun on the other side.

I think of it like balanced equation.

For this reason I eliminated everything but B & D, by looking at the answer choices only.

The idiom is such as vs. Such like. Whenever they are listing
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