The following data (in thousands of dollars) have been taken from the accounting records of Karling Corporation for the year just ended. Sales $990 Raw materials inventory, beginning $40 Raw materials inventory, ending $70 Purchases of raw materials $120 Direct labour $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 What was the cost (in thousands of dollars) of the raw materials used in production during the year? Select one: a. $90. b. $160. c. $190. d. $150.