Q. The national income of a country for a given period is equal to the (UPSC Prelims 2013)
Answer: money value of final goods and services produced
Notes: The correct answer is [D] money value of final goods and services produced. National income is a measure of the total economic activity of a country within a specific period (usually a financial year). While there are several ways to calculate it, the most fundamental definition refers to the total monetary value of all final goods and services produced within the economy.

• Final Goods and Services (Option [D] is Correct): To avoid the problem of "double counting," only the value of final goods is included. For example, the value of flour used to make bread is not counted separately if the value of the bread (the final product) is already included. This value, adjusted for net factor income from abroad, represents the National Income (often represented as NNP at factor cost).
• Produced by Nationals (Option [A] is Incorrect): While this describes Gross National Product (GNP), the term "National Income" in a technical sense (NNP at factor cost) requires specific adjustments like the deduction of depreciation. Option [D] is a more direct definition of the core economic output that constitutes the base of national income.
• Consumption and Investment (Option [B] is Incorrect): This refers to the Expenditure Method of calculating GDP (Y = C + I + G + (X - M)). While it is a way to measure national income, it does not define what national income is. Furthermore, this option omits government spending (G) and net exports (X - M), making it an incomplete representation.
• Personal Income (Option [C] is Incorrect): Personal income is the income actually received by individuals. National income includes things that individuals do not receive, such as corporate taxes and undistributed corporate profits, and excludes transfer payments (like pensions or unemployment benefits) which are included in personal income. Therefore, the two are not equal.