The following data has been provided by Moretta Corporation, a company that produces forklift trucks:

Budgeted production 3400 trucks

Standard machine-hours per truck 2.9 machine-hours

Standard supplies cost $1.50 per machine hour

Actual production 3800 trucks

Actual machine-hours 10930 machine-hours

Actual supplies cost (total) $17496

Supplies cost is an element of variable manufacturing overhead. The variable overhead efficiency variance for supplies cost is:

A) $135 U

B) $135 F

C) $966 U

D) $966 F