Final answer:
An auditor would least likely choose to examine purchase requisitions, receiving reports, and the inventory subsidiary ledger to ascertain recorded liabilities.
Step-by-step explanation:
An auditor would least likely choose to examine closely C) Purchase requisitions, D) Receiving reports, and E) Inventory subsidiary ledger in order to ascertain that all purchases incurred during the accounting period have been recorded as a liability.
Invoices (option A) provide evidence of the amount owed for a purchase, while purchase orders (option B) indicate the intent to purchase goods or services. These documents are commonly used to verify and record liabilities. However, purchase requisitions, receiving reports, and the inventory subsidiary ledger are not direct records of a liability and are less likely to be examined in the context of ascertaining recorded liabilities.