The correct answer is: C. both (a) and (b).
A debit entry is an entry made in the left-hand side of a ledger account, while a credit entry is an entry made in the right-hand side of a ledger account. Detected money errors are corrected by making a debit entry or a credit entry, or both, depending on the nature of the error.
For example, if a company mistakenly pays a supplier twice, the company will need to make a debit
entry to the cash account and a credit entry to the accounts payable account. This will reduce the amount of cash on hand and the amount owed to the supplier.If a company mistakenly receives payment from a customer twice, the company will need to make a credit entry to the cash account and a debit entry to the accounts receivable account. This will increase the amount of cash on hand and the amount owed by the customer.
In both of these examples, the company is correcting an error by making a debit entry or a credit entry, or both.