Coolidge's administration was marked by: a continuation of the post–world war i economic slump. continued tax breaks for the lower and middle classes at the expense of the upper class. prosperity. the creation of the internal revenue service, which drastically reformed taxation formulas and duty lists. a slow economic downturn.

Prosperity.

Calvin Coolidge was in office as president from 1923 to the spring of 1929.  In that period of the "Roaring Twenties," the country experienced great economic success -- in between the brief depression that followed World War I and the Great Depression that began with the stock market crash that occurred in the fall of 1929.

Your correct answer in c

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