Why are Keynesian academic economists so fearful of the gross output model?

A) All of the statements are correct

B) The Gross Output Model has shaken up the academic world in a higher education.Since most Keynesian academic professors have no real world business experience, it's hard for them to understand and appreciate the contributions of business and free market capitalism to society. They believe that top-down government policies and spending is still the best way to stimulate the economy and create national wealth.

C) The GO model shows that reliance on government spending to stimulate the economy is foolish.

D) The GO model clearly shows that private sector is much larger and more powerful versus the federal government to stimulate the economy, make it grow, and make actual wealth.