Which of the following must a bookkeeping system be able to show?

A bookkeeping system, particularly in the context of real estate and trust accounting, must provide a clear and accurate picture of the balance of the trust account. This is crucial for compliance with legal requirements, regulations, and the proper management of client funds.

Having a clear record of the balance helps ensure that all funds are properly accounted for and allows for easy reconciliation between the records of transactions and actual bank statements. Maintaining an accurate balance is vital because it reflects the financial status of the trust account at any given time, ensuring that funds are available for client disbursement when needed.

While the other options are important aspects of a bookkeeping system, they do not encompass the overarching requirement to maintain a clear view of the trust account's balance, which is essential for fiduciary responsibility and financial integrity in handling client funds.