Comprehensive and Detailed Explanation:
* Understanding the Ransomware Issue:
* The key issue here is thatbackups were not recoverable within the required RPO timeframe.
* This means the organizationdid not properly testitsbackup and disaster recovery (DR) processes.
* To prevent this from happening again, regular disaster recovery testing is essential.
* Why Option C is Correct:
* Disaster recovery testing ensures that backups are functionaland can meetbusiness continuity needs.
* Frequent DR testingallows organizations to identify and fixgaps in recovery strategies.
* Regular testing ensuresthat recoverymeets the RPO & RTO (Recovery Time Objective) requirements.
* Why Other Options Are Incorrect:
* A (Encrypt & label backup tapes):While encryption is important, it does not address thefailure to meet RPO requirements.
* B (Reverting to manual business processes):While amanual continuity planis good for resilience, it doesnot resolve the backup and recovery failure.
* D (Tabletop exercise & RACI matrix):Atabletop exerciseis a planning activity, butit does not involve actual recovery testing.