The correct answer is When a transaction is not recorded at allError of Omission: This type of error arises when an accountant completely or partially excludes or omits to record an entry in the books of accounts. Complete omission of entry does not affect the Trial Balance while partial omission affects the Trial Balance. For example: Payment of Electricity bill omitted to be recordedAdditional Information Other types of Errors in Accounting: Type of ErrorMeaningExampleError of principleThis type of error arises when the wrong accounting principle is applied while performing the Accounting activities. These errors do not affect the Trial BalanceTreating the purchase of an asset as an expense. Error of CommissionThis error arises when an accountant makes correct debit or credit of the accounts but makes mistake in entering the amount or posting to the wrong side in the ledger. Purchase of fixed assets for Rs. 10,000 posted to the credit of Vendor's account as Rs. 1000Compensating ErrorsWhen one error committed by an accountant compensates another error, it is called compensating error. Purchase of goods from Ram Rs. 1000 & Shyam Rs. 4000 recorded as Ram Rs 4,000 and Shaym Rs. 1,000