Answer
d. real, long
Work Step by Step
According to Classical analysis, developments in the economy's monetary system influence the nominal variables but not the real variables. Principle of monetary neutrality states that the changes in money supply do not affect the real variables such as real wage, real GDP etc.
In the short run, however, the money supply might affect real variables in the process of obtaining the long-run equilibrium. But in the long-run, the effect of the money supply is quite negligible on real variables.
