The Assembling Department of Patchwork, Inc. had 10,400 units in process on December 1 and received 30,500 units from the Sewing Department. During the month, it completed 21,000 units and transferred them to the Packaging Department. Calculate the number of units accounted for by the Assembling Department for December. The company uses the FIFO method. A. 19,900 units B. 30,500 units O C. 40,900 units OD. 10,400 units