Earl Co. was formed on January 2, 2007, to sell a single product. Over a two-year period, Earl's acquisition costs have increased steadily.

Earl Co. was formed on January 2, 2007, to sell a single product. Over a two-year period, Earl's acquisition costs have increased steadily. Physical quantities held in inventory were equal to three months' sales at December 31, 2007, and zero at December 31, 2008. Assuming the periodic inventory system, the inventory cost method which reports the highest amount of each of the following is

                           Inventory                 Cost of Sales

                   December 31, 2007              2008      

           a.                LIFO                          FIFO

           b.                LIFO                           LIFO

           c.                FIFO                          FIFO

           d.                FIFO                           LIFO

why the answer is C? can someone explain it plzz