Which of the following is not a type of unemployment?

Frictional, structural, and cyclical unemployment are established categories within economic theory that describe specific causes of unemployment within an economy.

Frictional unemployment refers to the short-term unemployment that occurs when individuals are temporarily between jobs or are entering the workforce for the first time. Structural unemployment arises from long-term changes in the economy that cause a mismatch between the skills of the labor force and the demands of employers. Cyclical unemployment relates to the fluctuations in the economy, typically rising during recessions when there is insufficient demand for goods and services.

In contrast, voluntary unemployment is not commonly regarded as a formal type of unemployment. It occurs when individuals choose not to work, perhaps because they are waiting for a more desirable job opportunity or because they prefer to leave the labor force under certain conditions. Since it does not fit within the defined categories of unemployment that are typically discussed in economic contexts, it is identified as the option that does not represent a recognized type of unemployment.