Identify the Inventory Valuation Method That Is Being Described for Each

Identify the inventory valuation method that is being described for each situation below. In all cases, assume a period of rising prices. Use the following to identify the inventory valuation method:
$$\begin{array} { | l | l | } \hline \text { FIFO } & \text { First in, first out } \\\hline \text { LIFO } & \text { Last in, first out } \\\hline \text { SI } & \text { Specific identification } \\\hline \text { WA } & \text { Weighted average } \\\hline\end{array}$$
a. The method that can only be used if each inventory item can be matched with a specific purchase and its invoice
b. The method that will cause the company to have the lowest income taxes
c. The method that will cause the company to have the lowest cost of goods sold
d. The method that will assign a value to inventory that approximates its current cost
e. The method that will tend to smooth out erratic changes in costs.