What must be true for a trial balance to be considered correct?

For a trial balance to be considered correct, total debits must equal total credits. This fundamental principle of double-entry accounting ensures that every transaction affects at least two accounts—one account is debited while the other is credited, maintaining the accounting equation's balance. When the total amount of debits matches the total amount of credits, it indicates that the books are in balance and there are no arithmetic errors in the recording of transactions. This is crucial for financial reporting as it serves as an initial check for accuracy before further financial statements are prepared.

The other options do not serve as valid criteria for a trial balance. For instance, stating that total debits must equal total assets does not reflect the requirement of balancing debits with credits, which is the core function of a trial balance. Similarly, requiring that all credits balance with cash reserves would not provide a comprehensive view of all accounts and their balances. Finally, while account balances needing to be positive may be true for certain accounts, it does not apply universally, especially for contra accounts or liabilities that can have negative balances.