Using a Compensating Differential Wage Theory, Why Do Some Individuals

Using a compensating differential wage theory, why do some individuals earn more than others?

A) Workers who earn more are more productive.
B) Workers need to earn more to be willing to accept dangerous working conditions.
C) Workers need to earn more to be willing to accept a safe indoor job.
D) Workers who are more educated and better trained are able to earn more than the equilibrium wage.
E) Workers who earn more tend to be concentrated in a single occupation.