Why Is It Unlikely That Income Inequality Could Ever Be

Why is it unlikely that income inequality could ever be eliminated?

A) Workers will always have the same skills,abilities,and productivities.
B) All jobs are roughly equal in their attractiveness to workers.
C) All workers are perfectly mobile.
D) Workers will always have different skills,abilities,and productivities.
E) Workers all share the goal of earning as much income as possible.