Minimum-wage laws dictate:

a. the exact wage that firms must pay workers.
b. a maximum wage that firms may pay workers.
c. a minimum wage that firms may pay workers.
d. both a minimum wage and a maximum wage that firms may pay workers.

A minimum wage that firms may pay workers (Option C)

Explanation:

A minimum wage is the lowest pay, wage or salary permitted by law for employers to pay their workers. In other words, a minimum wage is the price benchmark which workers should not go below in offering labor.  

Minimum wages are legally established to protect or guard workers against unduly low pay or exploitation. Most countries of the world have minimum wage legislation that was introduced before the end of the 20th century.

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