The following data (in thousands of dollars) have been taken from the accounting records of Karling Corporation for the just completed year. Sales: $990 Raw materials inventory, beginning: $40 Raw materials inventory, ending: $70 Purchases of raw materials: $120 Direct labor: $200 Manufacturing overhead: $230 Administrative expenses: $150 Selling expenses: $140 Work in process inventory, beginning: $70 Work in process inventory, ending: $50 Finished goods inventory, beginning: $120 Finished goods inventory, ending: $160 The cost of the raw materials used in production during the year(in thousands of dollars)was: a. $190. b. $90. c. $150. d. $160.