At the start of 2021, X Company developed the following budgeted total cost function: $8.76X + $226,600, where X is number of units produced. Budgeted production for the year was 10,500 units, but actual production for the year was 9,700 units. Actual total costs were $337,177. What was the 2021 flexible budget variance for total costs [a positive number means a favorable variance and a negative number means an unfavorable variance]? A: $-13,897 B: $-15,704 OC: $-17,746 OD: $-20,052 OE: $-22,659 OF: $-25,605