Detailed Explanation:

National Income represents the money value of all final goods and services produced within an economy during a given period (usually one year).

✅ Option 4 – Correct: Money value of final goods and services produced accurately defines National Income, avoiding double counting by excluding intermediate goods.

❌ Option 1 – Incorrect: Production by nationals refers to Gross National Product (GNP), not National Income which measures production within geographical boundaries.

❌ Option 2 – Incorrect: Consumption + Investment alone excludes Government expenditure (G) and Net Exports (X-M) from the full expenditure approach: Y = C + I + G + (X-M).

❌ Option 3 – Incorrect: Sum of personal incomes excludes corporate profits, undistributed earnings, and other factor incomes generated in production.