Sentence Correction (SC) | Re: In reference to the current hostility toward smoking, smokers frequent

Nothing here relies on memorized idioms.

The three middle choices (B, C, D) are ungrammatical, because they followabout —a preposition—with a complete sentence. (Like other prepositions,about can only be followed by a noun.)

Between A and E, you should notice that choice E uses an __ING modifier that takes the following subject as the subject/agent of the __ING action (Who was "referring
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