The actual cost of direct materials is $11.70 per kilogram. The standard cost per kilogram is $11.50. During the current period, 8,200 kilograms of direct materials were used in production and 18,300 kilograms were purchased. The standard quantity of direct materials for actual units produced is 18, 100 kilograms. How much is the direct materials efficiency variance? O A. $115,830 favourable OB. $113,850 unfavourable O c. $115,830 unfavourable OD. $113,850 favourable