Answer:
The correct answer is: Collective bargaining.
Step-by-step explanation:
Collective bargaining refers to the act in which employees, typically associated with labor unions, request employers certain benefits that were not included in their initial contracts. Those requests can be the result of the union believing the treat provided by the employer is unfair. In some cases, it could be true. Thus, the union representatives agree with the employer certain traits that could benefit them both.