Answer: Frictional: retired people and volunteer workers.
Step-by-step explanation:
Frictional unemployment is a constant in any economy. It´s caused by temporary employment transitions, as workers and employers may lack some information. For example, someone looking for their very first job may not have enough resources to find a suitable job and ends up not taking other employment, temporarily holding out. On the other hand, a business may refrain from hiring new employees if they think there´s no one enough qualified available when there actually is.