问题如下：
PZ company is a US-based company with US GAAP. PZ has two European subsidiaries: LI financial service and HE financial consultant. Felix, CFA, has prepared PZ’s forecasted financial statements in 2018:
Felix forcast LI financial service will report 3,500 in sales and 1,500 in cost of sales in 2018, If PZ chooses current rate method to translate LI's financial statements into US dollar and temporal method to translate HE's financial statements into US dollar. Both LI and HE use the FIFO method to account for inventory. Compared with the gross margins the subsidiaries reported in local currency, PZ’s consolidated gross margin will most likely:
选项：
A. be distorted if HE using the current method
B. not be distorted
C. be distorted because of the translation and inventory accounting methods
解释：
C is correct.
考点：current rate method and temporal method
解析：
题目问哪种情况的gross margin会被distorted，也就是问哪种情况下转换前后的gross margin不同。母公司的gross margin不存在转换问题，不用考虑，只需要分别考虑两个子公司。
gross margin=（sales-COGS）/sales
current rate method下，sales和COGS用的汇率是一样的，转换前后的gross margin是相同的，选项A说法错误。
由于LI和HE两个子公司的转换方法一个是current method，一个是temporal method，因此转换后的consolidated gross margin是不同于转换前的，选项B错误。
对于选项C，如果用temporal & FIFO的方法，那么sales用average rate转换，而COGS是用卖掉的存货采购时候的历史汇率转换的，FIFO方法下，COGS体现的是较早购买的存货的价值，转换也用较早购买存货时点的汇率。所以COGS和sales一个用historical rate 转换，一个用average rate转换，转换前后的gross margin不同，也就是被汇率distorted了，选项C正确。
本题如果将FIFO改为LIFO呢？是不是和LC汇率升值贬值有关？请讲解一下FIFO和LIFO下的current method 与temporal method下cogs的变化！
