A company's production department was experiencing a high defect rate on the assembly line, which was slowing down production and causing a higher waste of valuable direct materials. The production manager decided to recruit some highly skilled production workers from another company to bring down the defect rate. This would produce a(n) ________. A. unfavorable direct materials efficiency variance B. unfavorable direct labor efficiency variance C. unfavorable direct labor cost variance D. unfavorable direct materials cost variance