Final answer:
A Stocktake report is the correct document that reflects an inventory loss, as it reports actual stock levels after a physical count as compared to recorded figures, highlighting any discrepancies.
Step-by-step explanation:
When a business realizes an inventory loss, the document that typically reflects this loss is the C. Stocktake report. An inventory loss can become apparent after a physical count of the inventory, which may show discrepancies between the actual stock and the recorded stock levels. This physical count is documented in a stocktake report. An invoice is typically used to request payment for goods or services, a purchase order is a document sent to a supplier to order goods, and a payment receipt is proof of a payment made. None of these documents are primarily used to record losses of inventory, which is why the stocktake report is the correct document for reflecting inventory losses.