Which of the following is a key principle in ensuring data availability?

Implementing robust backup and recovery solutions is essential for ensuring data availability because it ensures that data remains accessible even in the event of a disaster, hardware failure, or data corruption. By having a reliable backup system in place, organizations can quickly restore lost data and maintain continuity in their operations. This principle directly addresses the need for consistent access to information, enabling users to retrieve essential data without significant downtime.

While the other options contribute to overall data security and integrity, they do not specifically target the objective of maintaining constant data availability. Restricting access to sensitive information enhances security but may inadvertently create barriers to availability if access controls are too stringent. Encrypting stored personal data protects the data's confidentiality and integrity but does not directly address the need for availability in the face of data loss. Conducting regular security audits is crucial for identifying potential vulnerabilities and ensuring compliance but does not inherently ensure that data can be quickly accessed when needed. Thus, robust backup and recovery solutions stand out as the most critical component of ensuring data availability.