Explanation:

- Determination of Income:

- The multiplier plays a central role here.

- It shows how initial changes in spending can lead to a larger change in income levels.

- Fiscal Policy:

- Government spending and tax policies use the multiplier effect.

- It helps gauge the total economic impact of fiscal decisions.

- Monetary Policy:

- Typically involves controlling money supply and interest rates.

- The concept of the multiplier isn't directly applied here.

- Foreign Direct Investment (FDI):

- Often targeted and specific to sectors, lacking broader multiplier effects.

- Effects on income and employment might not involve traditional multiplier analyses.

Correct Answer: Monetary policy