Which of the following is NOT a feature of a RAID system?

In a RAID (Redundant Array of Independent Disks) system, one of the defining features is its ability to combine multiple disk drives into a single unit to enhance performance and data protection. Options like increased data redundancy, improved data transfer speeds, and lower risk of data loss are all fundamental aspects of RAID configurations.

Increased data redundancy refers to the way RAID systems store copies of data across multiple drives. This ensures that if one drive fails, the data is still accessible from another drive. Improved data transfer speeds can be achieved through techniques like striping, where data is split across multiple drives, allowing for simultaneous read/write operations. The lower risk of data loss is inherently associated with redundancy; RAID can protect against the failure of a single or, depending on the configuration, multiple drives.

The concept of single drive functionality, however, does not align with the primary purpose of RAID, which is to operate multiple drives in conjunction. RAID configurations improve performance and redundancy by utilizing multiple drives, so highlighting a feature that focuses on a single drive contradicts the essential purpose of RAID. Thus, this choice correctly identifies a characteristic that is not inherent to RAID systems.