Brokerage Firms That Offered Money Market Security Accounts in the 1970s

Brokerage firms that offered money market security accounts in the 1970s had a cost advantage over banks in attracting funds because the brokerage firms

A) were not subject to deposit reserve requirements.
B) were not subject to the deposit interest rate ceilings.
C) were not limited in how much they could borrow from depositors.
D) had the advantage of all the above.
E) had the advantage of only A and B of the above.