Budgeted variable overhead for the year is $150,000. Expected activity is 30,000 standard direct labor hours. The actual hours worked were 15,000 and the standard hours allowed for actual production were 18,000. The variable overhead efficiency variance is:

a.$14,600 F.

b.$30,000 F.

c.$18,000 F.

d.$15,000 F.

e.None of these choices are correct.