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During December, Krause Chemical Company had the following selected data concerning the manufacture of Xyzine, an industrial cleaner:

All materials are added at the beginning of processing in this department, and conversion costs are added uniformly during the process. The beginning work-in-process inventory had $120 of raw materials and $180 of conversion costs incurred. Materials added during December were $540 and conversion costs of $1,484 were incurred. Krause uses the weighted-average process-costing method. The total conversion costs assigned to units transferred to the next department in December were:

a. $1664

b. $1600

c. $1513

d. $1484