Which of the following is not part of the double-entry system?

The double-entry system consists of ledger accounts to which transactions are posted using matching debit and credit entries, and these accounts are eventually closed off (balanced) at the end of a period. The Trading Account, Profit and Loss Account, and Appropriation Account are all genuine ledger accounts within this system: each receives closing entries transferred by double entry from other accounts, and each is itself balanced off.

The Balance Sheet, however, is not an account at all. It is a statement, a list of the balances remaining on the asset, liability, and capital accounts after the trading, profit and loss, and appropriation accounts have been closed off. No transactions are posted to or from the Balance Sheet using debit and credit entries; it simply displays balances that already exist in the ledger. For this reason, it is not part of the double-entry system in the way the other three accounts are.

A useful check: if a document receives its own double-entry postings and is itself balanced off within the ledger, it is part of the double-entry system; if it merely summarises balances already recorded elsewhere, as the Balance Sheet does, it sits outside that system.

Remember this distinction when a question separates "accounts" from "statements": Trading, Profit and Loss, and Appropriation Accounts are accounts; the Balance Sheet is a statement of balances.