Scenario: A security audit reveals unauthorized access attempts in a DB2 database. What steps should the DBA take to investigate and mitigate potential security risks?

The correct option is to review database logs to identify the source and nature of unauthorized access attempts. Database logs often contain valuable information about login attempts, failed authentication, and suspicious activities, which can help the DBA understand the scope of the security breach and take appropriate actions to mitigate risks. Implementing two-factor authentication, temporarily disabling access, or enhancing firewall restrictions are valid security measures but may not directly address the ongoing security breach.