Answer :
The correct answer is A) collective bargain.
Labor Unions did not accomplish collective bargains for the workers.
In labor, a collective bargain is a process, a negotiation process between an employer an employees to discuss some issue at the workplace. A union member represents the workers, is the voice of the workers in the conversations with the employer. During the bargain moment, both parties talk about wages, risks in the working environment, working conditions, possible layoffs, and motivation and attitude of the workers.