Economists Working in Both Keynesian and Monetarist Traditions Believe Each

Economists working in both Keynesian and monetarist traditions believe each of the following is a key element in understanding business cycles except

A) the need to understand the determinants of nominal aggregate demand.
B) the need to understand the division of changes in nominal aggregate demand into changes in production (and employment) and changes in prices (inflation or deflation) .
C) real fundamentals effectively determine the values of real quantities like GDP even in the short run.
D) the need to understand the velocity of money, the determinants of investment spending, the multiplier, . crowding out, the natural rate of unemployment, the rate of expected inflation, and the Phillips curve.