Answer:
4. the normal process of jobs being created and destroyed.
Explanation:
Frictional unemployment is unemployment that is related to switching of jobs also called transitional unemployment. It occurs when workers leave jobs and get jobs as a result of normal labor tunover in a healthy economy.
In a growing economy frictional unemployment is the lowest type of employment bad there are abundant opportunities for workers.
Quitting a job is a voluntary type of frictional unemployment, while when an employee bis fired it is involuntary type of frictional unemployment.