Final answer:
The part of the variable overhead budget variance due to the difference between actual and standard hours is called the variable overhead efficiency variance.
Step-by-step explanation:
The part of the variable overhead budget variance due to the difference between actual hours required and standard hours allowed for the work done is called the variable overhead efficiency variance.
For example, let's say the standard hours allowed for a particular job are 8 hours, but the actual hours required to complete the job are 10 hours. The difference of 2 hours would be considered the variable overhead efficiency variance.