GMAT Sentence Correction (SC) | Re: Retail sales rose 8/10 of 1 percent in August, intensifying

Here "double" is a verb. Consider first a simple example as below:

The increment doubled mysalary.

The increment doubledmy $200 salary of last year .

Now compare the above with option B:

Personal spending would doublethe 1.4 % growth rate .

There is no grammatical comparison here. Option B just states that the personal spending
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