A Local Bank Sells Two Services, Cheque Accounts and ATM

A local bank sells two services, cheque accounts and ATM card services. Mr Donethat is willing to pay $8 a month for the bank to service his cheque account and $2 a month for unlimited use of his ATM card. Ms Beenthere is willing to pay only $5 for a cheque account but is willing to pay $9 for unlimited use of her ATM card. To keep this example simple, assume that the bank can provide each of these services at zero marginal cost.
-According to the information provided, how much additional profit does the bank make when it switches to use of a tying strategy to price cheque account and ATM services?

A) $14
B) $8
C) $10
D) $1