Why did Roosevelt want to change the number of Supreme Court justices from 9 to 15?

Select one:
a. He hoped to settle disputes that were occurring between the 9 justices.
b. He wanted to appoint 6 new justices who supported New Deal programs.
c. He felt the importance of the decisions the court made were too much for just 9 justices.
d. He wanted to balance the court by appointing more Republican justices.