The principal book Ledger contains all types of accounts, including personal, real, and nominal accounts. It is used to record all financial transactions of the business.
Step 1: Analyzing each option.
(A) All accounts: Correct. The ledger records all accounts: personal, real, and nominal.
(B) Personal accounts only: Incorrect. The ledger does not only contain personal accounts.
(C) Only real accounts: Incorrect. The ledger contains all types of accounts, not just real accounts.
(D) Nominal accounts are the only ones: Incorrect. The ledger records all accounts, not just nominal accounts.
Step 2: Conclusion.
Therefore, the correct answer is (A), as the ledger contains all accounts.
Final Answer:} All accounts.