Final answer:
The ending inventory and cost of goods sold will be the same under both perpetual and periodic systems when using the FIFO method because this method assumes the oldest inventory is sold first, unaffected by how inventory changes are recorded.
Step-by-step explanation:
The question pertains to whether the ending inventory and cost of goods sold (COGS) will be the same under a perpetual or periodic system for different inventory valuation methods. When using the First-In, First-Out (FIFO) method, both perpetual and periodic systems will have the same ending inventory and cost of goods sold because this method assumes that the oldest inventory items are sold first, regardless of which system is used to record inventory changes.
Under the FIFO method, even if the tracking of inventory happens continuously (perpetual system) or at the end of the period (periodic system), the oldest cost layers are removed first, which leads to the same COGS and ending inventory in normal circumstances, without considering other factors like theft, spoilage, or errors. Therefore, the answer to the student's question is: a. FIFO method.