Please write out correct answer and whether it's A, B, C or D. Thank you.

Vintage Audio Inc. manufactures and assembles speakers in a just-in-time cell. The company budgeted for 1,000 speakers for the month. Conversion costs for 1,000 units were applied to the speaker assemblies at a conversion cost of $12.60 per unit. Only 990 speakers were completed and moved to the finished goods storeroom by the end of the month. Using just-in-time costing, the cell efficiency variance would be O $12,474 favorable O $ 126 unfavorable O $ 126 favorable $ 12,474 unfavorable