Which event is most likely to necessitate further investigation?

Choosing "Error" as the most likely event to necessitate further investigation is valid because errors typically indicate a failure or malfunction within a system that could lead to degraded performance, potential data loss, or security vulnerabilities. When an error occurs, it signals that something is not functioning as expected, warranting a closer look to identify the root cause and implement solutions to rectify the issue. Understanding the specifics of the error helps maintain system integrity and reliability.

In contrast, success indicates that a process or operation has completed successfully, and while it might provide insights into what works well, it does not inherently require further investigation. Information often serves as a general status update or data report, which typically does not necessitate additional scrutiny unless it highlights a specific issue. An audit is a review process that generally evaluates compliance or performance over a period of time; while it can uncover issues, it is typically a planned event rather than a spontaneous trigger for investigation. Thus, "Error" stands out as the event that directly indicates the need for further examination.