Question

Which best explains why collective bargaining increases the bargaining power of workers?

Answer 1

The answer to this question is It's difficult for employers to replace their entire work force.

Answer 2

In the above question, options are not given so the answer has been generalized.

Collective bargaining power gives rights to the workers to put their demands in front of employer in a better way. It puts the workers and employers on the same level.
Collective bargaining increases the power of bargaining of workers. If the workers and employers have agreed on a collective bargaining on mandatory subjects then it is unfair for the employer to refuse.