How Do You Explain Why Income Inequality in the United

How do you explain why income inequality in the United States has been increasing?

A) New technologies raise the MRP of educated workers, while having no (or a much smaller effect) on the MRP of uneducated workers.
B) The MRP of rich workers increases more slowly than the MRP of poor workers.
C) The labor supply of poor workers shifts to the left, while the labor supply of rich workers shifts to the right.
D) Many talented U.S. workers, earning high incomes, are lured away by firms located in other countries that are paying considerably higher wage rates.
E) Minimum wage laws have raised the minimum wage rates.