Which of the following is NOT one of the six specialty journals?

The correct choice is based on the understanding of specialty journals and their purposes within accounting practices. Specialty journals are designed to streamline the recording of specific types of transactions, leading to more efficient processing and less complexity in bookkeeping.

The cash receipts journal is dedicated to recording all cash inflows, providing an organized method to track revenue generated from various sources. The sales returns journal specifically records any returns made by customers, thereby tracking inventory and ensuring accurate sales figures. The purchase journal is utilized for documenting all credit purchases, which helps in managing expenses related to inventory acquisition and ensuring accurate accounts payable.

The term "expense journal" is not recognized as one of the typical specialty journals. Instead, expenses are usually recorded in a general ledger or among various expense accounts, rather than through a dedicated journal. Consequently, it is the only option that does not align with the established categories of specialty journals, affirming that it is indeed not one of the six specialized journals used in accounting.