Which of the following provides high availability of data?

RAID configurations such as RAID 1 (mirroring) and RAID 5/6 (striping with parity) keep data continuously accessible by distributing it or duplicating it across multiple disks. If any single disk fails, the array reconstructs or directly serves the data from the remaining drives without interruption, satisfying the definition of high availability. This makes RAID the standard hardware-level mechanism for ensuring storage remains online during drive failures.

Anti-virus software detects and removes malware but provides no redundancy or fault tolerance for storage hardware failures, so it does not contribute to data availability.

EFS (Encrypting File System) protects data confidentiality by encrypting files at rest but does nothing to ensure the data remains accessible if a drive or system component fails.

Backup is a recovery mechanism used to restore data after a loss event and typically requires significant downtime to complete the restore process, making it a recovery tool rather than a high-availability solution.