In macroeconomics, the economic growth of a country is most commonly measured in terms of which of the following indicators?

Introduction / Context:
Economic growth is a central concept in macroeconomics, referring to an increase in a country's output over time. Policymakers, analysts and media reports often quote growth figures, and these are usually based on changes in Gross Domestic Product. Examination questions therefore expect candidates to know that growth is commonly measured by the percentage change in real GDP over a period, typically a quarter or a year. Understanding this measure helps you interpret economic news and policy discussions correctly.

Given Data / Assumptions:

• The question asks for the indicator most commonly used to measure economic growth.
• GDP is the total value of final goods and services produced within a country.
• Growth rates are usually expressed as a percentage change over time.
• Per capita income is related but introduces population into the calculation.

Concept / Approach:
In practice, economic growth is typically measured as the percentage rate of increase in real GDP, that is GDP adjusted for inflation. When reports mention that an economy grew by a certain percentage in a year, they are almost always referring to growth in real GDP. Per capita income growth is an important indicator of improvements in average living standards, but the basic term economic growth is tied directly to the expansion of total output or GDP. Government expenditure growth is only one component of GDP and does not capture overall output growth by itself.

Step-by-Step Solution:
Step 1: Recall that economic growth is defined in textbooks as an increase in a nation's output of goods and services.Step 2: Recognise that total output is measured by real GDP.Step 3: Note that growth rates are expressed as percentage changes in this GDP from one period to the next.Step 4: Select the option that explicitly refers to the percentage rate of growth of GDP.

Verification / Alternative check:
You can cross check by thinking about how economic news is reported. Headlines commonly state that a country's economy grew by a certain percent in a given quarter or year. Detailed stories then clarify that this number represents the change in real GDP. When analysts discuss whether growth is strong or weak, they are comparing these GDP growth rates over time or between countries. This confirms that percentage growth in GDP is the standard measure.

Why Other Options Are Wrong:
Option B, growth of Net Domestic Product only, is not the usual headline indicator, even though NDP is conceptually related. Option C, growth of government expenditure, is incomplete because it covers only one part of GDP and does not reflect changes in private consumption, investment or net exports. Option D, growth of per capita income, is closer to a measure of economic development or change in average living standards, not the basic macro level concept of economic growth. Only option A correctly states that economic growth is most commonly measured by the percentage rate of growth of GDP.

Common Pitfalls:
Candidates may confuse growth with development and therefore choose per capita income as the measure. While per capita income is important, it is more closely linked to economic development and welfare. Another pitfall is to focus on one sector, such as government spending, and assume that its growth alone defines overall growth. To avoid these errors, remember that growth is about total output, so you should associate it with GDP, and growth rate with the percentage change in this GDP over time.

Final Answer:
Economic growth is most commonly measured by the percentage rate of growth of Gross Domestic Product.