问题如下：
3.Redline’s consolidated gross profit margin for 2007 would be highest if Acceletron accounted for inventory using:
选项：
A. FIFO, and its functional currency were the US dollar.
B. LIFO, and its functional currency were the US dollar.
C. FIFO, and its functional currency were the Singapore dollar.
解释：
A is correct.
Because the US dollar has been consistently weakening against the Singapore dollar, cost of sales will be lower and gross profit higher when an earlier exchange rate is used to translate inventory, compared with using current exchange rates. If the Singapore dollar is the functional currency, current rates would be used. Therefore, the combination of the US dollar (temporal method) and FIFO will result in the highest gross profit margin.
考点：不同的会计方法对财务比率的影响
解析：根据题目的表格首先明确US dollar 相较于Singapore dollar一直在贬值。即新加坡元升值。因为新加坡元是温和通胀的，因此物价是上涨的。
新加坡元两种汇率下revenue都是用average rate转换，没有差异，因此只需要比较COGS。如果想要gross profit margin 最大，那么我们要让cost of sales最小。
A选项FIFO&temporal method，对应的是较小的COGS和较低的汇率。
B选项LIFO&temporal method，对应的是较大的COGS和较高的汇率。
C选项FIFO¤t method，对应的是较小的COGS和average的汇率。
因此A选项的COGS转换后最低。 所以选项A正确。
将该类涉及cogs的题目分为两个步骤 1.先判断FIFO和LIFO情况下不考虑汇率问题假设物价水平是上涨的，FIFO情况下的cogs最小，LIFO情况下的cogs最大； 2.判断function currency是升值还是贬值决定使用current method 还是tempol method 这个思路对吗？