The principal lag for monetary policy

A、 and fiscal policy is the time it takes to implement policy.;
B、 and fiscal policy is the time it takes for policy to change spending.;
C、is the time it takes to implement policy. The principal lag for fiscal policy is the time it takes for policy to change spending.;
D、is the time it takes for policy to change spending. The principal lag for fiscal policy is the time it takes to implement it.