The Union's Manpower Advantage Over the Confederacy

The Union's manpower advantage over the Confederacy

A) was short-lived once the Confederacy began using slaves as soldiers.
B) proved essential for the success of Grant's attrition strategy.
C) was rather slight.
D) although substantial, did not matter in determining the war's outcome.
E) existed only because the Union had lower draft requirements than the Confederacy.