NO.PZ2018062004000149
问题如下：
Assuming a periodic inventory system, company M adopts the FIFO method, usually its inventory can not be sold out. When the purchasing price of inventory tends to rise, which of the following is true?
选项：
A.The gross profit margin will be lower if company M changes to LIFO method.
B.The gross profit margin will be higher if company M changes to LIFO method.
C.The gross profit margin will be the same if company M changes to LIFO method.
解释：
A is correct. When price rises, the LIFO method will lead to larger cost of sales, and then resullt in lower gross profit margin.
请问这道题periodic inventory system这个条件用的上吗？如果改成perpetual答案还一样吗？
