The stock records of Grift Company for January are as follows: 1 January 12 January Stock on hand of 40 000 units at $6 cost each = $240 000 Sale of 25 000 units at $10 selling price each = $250 000 Purchase of 15 000 units at $8 cost each = $120 000 Stock on hand 30 000 units 15 January 31 January In accordance with a periodic inventory system using first-in-first-out (FIFO), the COGS expense for January is calculated as follows: Select one: a. 25 000 units x $6 each = $150,000 O b. 25 000 units x $10 each = $250 000 O c. $240 000 + $120 000 - $180 000 = $180 000 O d. $240 000 + $120 000 - $210 000 = $150 000