GMAT Sentence Correction (SC) | Re: The Nobel Prize in chemistry was awarded to three scientists

B says:that plastic can be made electrically conductive—this advance leading

Generally speaking, whenthis (ademonstrative pronoun ) refers to somethingwithin the sentence itself, it is almost always incorrect. For example, in this case,this advance is referring to a fact already mentionedwithin the sentence : that plastic can be made electrically conductive.

Basically it seems to be a matter ofstylistic preference of GMAT. I did a quick scan of OG-13 and found 3 more such
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