Belle Auto Detailing reported the following results for the past week: Actual number of cars detailed Actual direct labor hours used Actual total direct labor cost 240 720 $6,900 Budgeted number of cars to be detailed Standard direct labor cost per hour Standard direct labor per car 320 $9.54 2.5 What is Belle's direct labor efficiency variance? O A. $1,145 unfavorable O B. $1,145 favorable O c. $1,150 unfavorable OD. $1,150 favorable