Choice "C" is correct. Under FIFO, the first costs inventoried are the first costs transferred to cost of goods sold. In a period of rising prices, FIFO results in the lowest cost of goods sold and the highest net income.
Choice "a" is incorrect. Under all LIFO methods, the last costs inventoried are the first costs transferred to cost of goods sold. In a period of rising prices, LIFO results in the highest cost of goods sold and the lowest net income.
Choice "b" is incorrect. In a periodic inventory system, the weighted-average method results in net income that is lower than FIFO net income and higher than LIFO net income when prices are rising.
Choice "d" is incorrect. In a perpetual inventory system, the moving-average method results in net income that is lower than FIFO net income and higher than LIFO net income when prices are rising.