Bulluck Corporation makes a product with the following standard costs: Standard Quantity or Hours 4.50 grams 0.50 hours 0.50 hours Direct materials Direct labor Variable overhead Standard Price or Rate $ 2.00 per gram $21.00 per hour $ 3.00 per hour The company reported the following results concerning this product in July. Actual output Raw materials used in production Actual direct labor-hours Purchases of raw materials Actual price of raw materials purchased Actual direct labor rate Actual variable overhead rate 4,000 units 12,370 grams 1,750 hours 13,100 grams $ 2.20 per gram $ 12.40 per hour $ 3.10 per hourThe company applies variable overhead on the basis of direct labor-hours. The direct materials purchases variance is computed when the materials are purchased. The variable overhead efficiency variance for July is:.A. 750 FB. 775 UC. 775 FD. 750 U