Which of the following is NOT a debit memorandum that should be deducted from the cash account?

In this context, the question revolves around understanding what constitutes a debit memorandum and its effect on the cash account. A debit memorandum typically represents amounts that will be deducted from the cash account, essentially reducing the balance.

Bank service charges, certified checks, and safe-deposit box fees are all expenses or fees that the bank charges to the account holder and therefore result in a reduction of the account balance. These items are considered debit memorandums because they reflect costs incurred by the bank that the account holder must cover, leading to less cash available in the account.

In contrast, the interest earned on balances is an income item for the account holder. Instead of serving as a deduction from the cash account, it is typically credited to the cash account, thereby increasing the overall cash balance. This is why it is identified as NOT being a debit memorandum that should be deducted. Understanding the distinction between credits and debits in terms of how they affect the cash account is crucial for accurate accounting practices.