Which Scenario Best Explains the Keynesian Transmission Mechanism When the Investment

Multiple Choice

Which scenario best explains the Keynesian transmission mechanism when the investment demand curve is vertical?

A) The interest rate falls,investment falls even more,the AD curve shifts rightward,but total expenditures do not change.
B) The interest rate falls,investment rises,total expenditures rise,and the AD curve shifts rightward.
C) The interest rate falls,investment falls instead of rising,and the AD curve ends up shifting leftward.
D) The interest rate falls,but investment does not respond; there is no change in total expenditures and no shift in the AD curve.