Steep Enterprises machines heavy-duty brake rotors that are used on commercial airliners. Steep's management developed the following standard costs: Standard direct labor hours per rotor 2.5 Standard variable overhead rate per direct labor hour $10.75 Actual activity for October Actual variable overhead costs incurred $156,000 Actual direct labor hours 12,000 Actual rotors machined 4.400 What is the variable manufacturing overhead officiency variance in October? O A $10,750 unfavorable OB. $27,000 unfavorable O C. $10,750 favorable OD. $27,000 favorable