Given:
Balance: 1,500
Issued: 25 checks.
interest per month: 0.5%
Based on the problem, the charges will only take effect if the remaining balance will fall below the minimum maintaining balance of 1,200 and additional charges will be given if her balance fall below 66. Since, she did not fall below maintaining balance she will merely earn interest.
1,500 * 0.5% = 7.50 Choice D.