Which economic measure assesses the value of all goods and services produced in a country?

Gross Domestic Product (GDP) is the correct choice because it represents the broadest measure of economic activity in a country. It calculates the total monetary value of all finished goods and services made within a country's borders in a specific time period, typically annually or quarterly. This includes all private and public consumption, investments, government outlays, and exports minus imports.

The relevance of GDP lies in its ability to provide a snapshot of a nation's economic performance and is commonly used by policymakers, economists, and analysts to gauge the overall economic health and growth trends of a country. In contrast, the Consumer Price Index measures inflation by tracking price changes of a basket of consumer goods and services, while Net National Product accounts for the depreciation of capital goods, and the Employment Rate focuses on the proportion of the labor force that is employed, which does not directly measure total production.