In a Given Market, Women with the Same Skills as Men

In a given market, women with the same skills as men earn less. Which of the following would suggest that the main source of the discrimination are the managers that must work with them?

A) Managers working with women must be paid more.
B) Companies with managers who hire more women make a larger profit.
C) Companies hiring women offer more day care and other amenities favored by women.
D) All of the above.