Certificate of Cloud Security Knowledge (CCSK) Practice Test 2025 - Free CCSK Practice Questions and Study Guide

The answer focuses on methods that guarantee data cannot be retrieved from disks once a virtual machine (VM) has been moved. Zeroing involves overwriting the disk space with zeros, effectively eliminating previously stored data by replacing it entirely. This method is particularly effective in ensuring that no remnants of the original data remain, making recovery impossible.

Encryption, while crucial for data protection during storage and transit, does not inherently prevent data recovery on a disk that has been moved without additional measures. If the key to access the encrypted data is retained or accessible, the data can potentially be decrypted and recovered.

The choice of compression or deduplication focuses on reducing the amount of data stored but does not address data recoverability. Backup or replication solutions create copies of data for recovery purposes, which also does not prevent retrieval of the original data. Fragmentation and over-provisioning pertain to the arrangement and allocation of storage but do not inherently ensure that data cannot be recovered.

Thus, the combination of zeroing and encryption highlights a robust approach to ensuring that data is unrecoverable and that any sensitive information is adequately safeguarded during the lifecycle of the VM.