Which One of the Following Observations Would Tend to Widen

Which one of the following observations would tend to widen the dispersion of earnings?

A) Banks charge higher interest rates on educational loans to those individuals most likely to face discrimination on the job
B) Those with higher ability face higher costs of investment funds
C) Human capital investment demand and supply curves are negatively correlated
D) Poor families pay a larger proportion of family income on education than rich families