If We Were to Compare the Annual Earnings of Union

If we were to compare the annual earnings of union and nonunion workers in recent years, we would find that

A) unions have not succeeded in raising the annual incomes of their members.
B) unions have succeeded in raising the annual incomes of their members.
C) the data is incomplete to tell whether unions have been successful in raising the annual income of their members.
D) union members have annual incomes substantially below nonunion members.