When Hiring Additional Workers, a Firm Operating in a Perfectly

When hiring additional workers, a firm operating in a perfectly competitive labor market will

A) have to offer higher wages to hire additional workers, but the old workers do not get the higher wage.
B) have to offer higher wages to hire additional workers, and the old workers will also receive the new, higher wage.
C) be able to hire additional workers without offering higher wages.
D) be able to hire additional workers at lower wages because the new workers have been unemployed.