The correct answer is: D. wage premium
A wage premium is a higher wage paid to workers who have certain characteristics, such as higher levels of education or experience. It can also be paid to workers who work in certain industries or occupations that are considered to be more difficult or dangerous.
Wage premiums are important because they help to attract and retain qualified workers. They also help to ensure that workers are fairly compensated for their skills and contributions.
Option A, workers premium, is incorrect because it is not a specific term used to describe wages paid to workers.
Option B, overtime premium, is incorrect because it is a premium paid to workers who work more than the standard number of hours.
Option C, factory premium, is incorrect because it is not a specific term used to describe wages paid to workers.