X Company's 2018 budgeted cost function for variable overhead was C=$10.20X, where X is the number of units produced, and its budgeted cost function for fixed overhead was C=$199,700. The following information is also available for 2018: Master Budget Actual Results Production 10,400 units 11,300 units Total variable costs $106,080 $133,637 Total fixed costs $199,700 $199,025 What was the total overhead flexible budget variance for 2018 [a positive number means a favorable variance and a negative number means an unfavorable variance]? A: $-11,053 B: $-12,932 C: $-15,130 D: $-17,702 E: $-20,711 F: $-24,232 G: $-28,352 H: $-33,172