The correct answer is B.
When the invesment of public funds in infraestructure projects increases, then the state is conducting a expansionary fiscal policy. It actually enhances employment figures directly, because people need to be employed to conduct those projects. Moreover, these people start earning a salary and demanding higher quantities of goods and services, therefore triggering the increase of production in other sectors and the need for more workers there too.
- Both A and C could achieve the desired result of increasing employement, but they are both mechanism of the monetary and not fiscal policy.
- D would cause the opposite result. It describes a tool for a contractionary fiscal policy.