Foster Manufacturing uses a standard cost system. Standards for direct materials are as follows: Direct materials (pounds per unit of output) Cost per pound of direct materials 15 $12 The company produced 100 units and actually used 1,600 pounds of direct materials. What is the journal entry to record the materials usage? O A. Work - in Process Direct Materials Efficiency Variance Raw Materials Inventory 19,200 1,200 20,400 19,200 OB. Work - in Process Direct Materials Efficiency Variance Raw Materials Inventory 1,200 18,000 O C. Work - in Process Direct Materials Efficiency Variance Raw Materials Inventory 18,000 1,200 19,200 20,400 O D. Work - in Process Direct Materials Efficiency Variance Raw Materials Inventory 1,200 19,200