An application’s audit trail is a record of all actions or events that occur within or affect an application, such as user activities, system operations, data changes, errors, exceptions, etc. An audit trail can provide evidence and accountability for an application’s functionality and performance, and support auditing, monitoring, troubleshooting, and investigation purposes. An IS auditor should ensure that an application’s audit trail has adequate security, which means that it is protected from unauthorized access, modification, deletion, or disclosure. Adequate security can help ensure that an audit trail maintains its integrity, reliability, and availability, and prevents tampering or manipulation by attackers or insiders who want to hide their tracks or evidence of their actions. Logs all database records is a possible feature of an application’s audit trail, but it is not the most important thing for an IS auditor to ensure, as logging all database records may not be necessary or feasible for some applications, and may generate excessive or irrelevant data that can affect the storage or analysis of the audit trail. Is accessible online is a possible feature of an application’s audit trail, but it is not the most important thing for an IS auditor to ensure, as online accessibility may not be required or desirable for some applications, and may introduce security or privacy risks for the audit trail. Does not impact operational efficiency is a desirable outcome of an application’s audit trail, but it is not the most important thing for an IS auditor to ensure, as operational efficiency may not be the primary objective or concern of an application’s audit trail, and may depend on other factors or trade-offs such as storage capacity, performance speed, or data quality.