Which type of event is essential for tracking changes made to a system?

The chosen answer, Audit, is correct because audit events are specifically designed to track and record changes made to a system. These events provide critical information about user actions and system modifications, enabling administrators to review what changes occurred, when they occurred, and who implemented them. This level of monitoring is vital for maintaining security, ensuring compliance with regulations, and facilitating troubleshooting.

In contrast, warning, error, and information events serve different purposes. Warning events indicate potential issues that could arise but do not necessarily imply that a change has taken place. Error events indicate failures or problems that occur within the system, which are often unexpected and may require immediate attention, but they do not track changes systematically. Information events, while helpful in providing context about routine operations, do not focus on tracking changes and their implications in the same way that audit events do. Thus, the audit category is essential for a comprehensive understanding of system changes and accountability.