Answer:
The correct answer is the option D: decrease; increase; increase.
Explanation:
On one hand, the monetary transmission mechanism is the process by which general economic conditions tend to change in order to affect the whole economy performance, and it changes as a result of changes in the monetary policy decisions.
On the other hand, the Keynesian model states that according to the monetary transmission mechanism a change in the aggregate demand could happen due to a change in the interest rate. Moreover, that monetary policy establishes that an increase in the money supply causes a decrease in the interest rate and therefore an increase in investment, which in turn causes an increase finally in total expenditures and aggregate demand.
