Please answer this question! Thank you!

Which of the following would produce a favorable labor efficiency variance?

A) Use of persons with low hourly wage rates in tasks where the standard is for high hourly wage rates.

B) Use of persons with high hourly wage rates in tasks where the standard is for low hourly wage rates.

C) Working more hours than the standards called for in completing a job.

D) Working fewer hours than the standards called for in completing a job.