GMAT Critical Reasoning (CR) | Re: ACME Midwest Sales Manager: I am unhappy to report that

The answer should be C
C) assumes an increase in sales percentage resulted from increased performance

increase in sales percentage can resulted from decreased numbers of other sales offices
For example:
Previous quarter: Midwest office had $90M (90%), South office $10M (10%)
Current quarter: Midwest reduced to $30M (75%), South stay the same $10M (25%)

As a result proportion of sales of the South office increased from 10% to 25%, but absolute number is the same

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