What describes a one-for-one checking control procedure?

A one-for-one checking control procedure is characterized by the individual matching of a specific document with a detailed listing of documents processed by the system. This means that for every document, there is an expected record on the listing confirming that it has been processed. This technique serves as a verification measure, ensuring that each transaction is accounted for and that no documents were lost or overlooked during processing. Such a procedure is crucial in maintaining the integrity of data and ensuring that all entries are properly recorded.

In contrast, the other options refer to different concepts. Backing up data files is a general risk management strategy and does not pertain specifically to the matching of individual documents. Similarly, enhancing software upgrade effectiveness focuses on the improvement of software deployment and does not involve document verification. Scanning databases for unauthorized access is unrelated to document checking and deals with security measures instead. Thus, option A is the one that accurately describes a one-for-one checking control procedure.