Variable overhead is applied in the basis of standard direct labor-hours. If the direct labor efficiency variance is unfavorable, the variable overhead efficiency variance will be?

a Favorable
b unfavorable
c zero
d indeterminable

The Variabel overhead efficiency is directly relatable to Direct Labour Hours

Therefore a direct relationship exists between
Direct Labour Hours &
Variable Overhead Hours.

Varibale overhead effciency variance is directly relatable to Direct Labour hours, if there is no IDLE TIME HOURS.

The answer to your question is ( b )