The static budget, at the beginning of the month, for Divine Dcor Company, follows: Static budget: Sales volume: 1,100 units; Sales price: $70 per unit Variable costs: $32 per unit; Fixed costs: $38,000 per month Operating income: $3,800 Actual results, at the end of the month, follows: Actual results: Sales volume: 990 units; Sales price: $74 per unit Variable costs: $35 per unit; Fixed costs: $34,100 per month Operating income: $4,510 Calculate the flexible budget variance for sales revenue. A. $3,960 U B. $3,960 F C. $4,890 F D. $4,890 U