Answer:
Closed shop
Step-by-step explanation:
A closed shop involves an agreement where the employer only recruits Union members. The workers must remain Union members as long as they work with the employer.
Legality of closed shop varies from country to country.
I'm this instance, Atalanta Industries agrees to hire only those workers who were already members of the Electrical Union. This is a closed shop situation.
Closed shop was declared illegal by the Taft-Hartley act in 1947.