GMAT Sentence Correction (SC) | Although the restaurant company has recently added many new

B. Wrong use of tense for the verb "increased". The correct tense should be present perfect, because the effect of increase is still there. Note the use of present perfect "have declined" in the non-underlined part, indicating that the effect of decline ( and hence that of increase as well) is still there.

C. Same tense issue as described for B above.

D. The conjunction although should
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