A company's flexible budget for 48,000 units of production showed variable overhead costs of $72,000 and fixed overhead costs of $64,000. The company incurred overhead costs of $122,800 while operating at a volume of 40,000 units. The total controllable cost variance is: A) $ 1,200 favorable. B) $ 1,200 unfavorable. C) $13,200 favorable. D) $13,200 unfavorable. E) $15,200 favorable.