Answer:
d. frictional unemployment
Explanation:
Frictional unemployment is the type of employment associated with people who are intentionally unemployed, as a result of searching for a better and well paid job. It is called search and wait unemployment because of the time delay workers have to wait before getting a new job.
This type of unemployment usually occur in a health economy which is due to an economy's employment transition. Here, workers who are changing their jobs and those who will be hired for the first time constitute what is called frictional unemployment.