Which of the Following Is an Endogenous Variable in the Dynamic

Multiple Choice

Which of the following is an endogenous variable in the dynamic model of aggregate demand and aggregate supply?

A) $\pi$ _t, inflation
B) $\pi _ { \mathrm { t } } ^ { \mathrm { * } }$ central bank's inflation target
C) $\rho$ , the natural rate of interest
D) $\pi$ _{t - 1}, previous period's inflation