The following standards for variable manufacturing overhead have been established for a company that makes only one product: 3.5 hours Standard hours per unit of output Standard variable overhead rate $ 15.20per hour following data pertain to operations for the last month: 3,800 hours hours 59,090 Actual total variable manufacturing overhead cost Actual output 80units What is the variable overhead efficiency variance for the A) $16,530 u B) $15.200 u C) $15,550 u D) $980 F