Network Defense Essentials (NDE) Practice Exam

The principle prioritized when ensuring data is backed up and accessible is availability. This principle emphasizes that data should not only be stored but also be readily accessible when needed. This involves implementing solutions that safeguard against data loss, such as regular backups and redundancy systems, which ensure that users can retrieve their data without undue delay.

In a network defense context, availability is crucial for maintaining business operations and services, as it ensures that users can access necessary information at any time. When backups are performed, it's not just about having copies of data; it’s also about making sure those copies are accessible and usable when required.

While integrity, nonrepudiation, and confidentiality are all important elements of data security, they each focus on different aspects. Integrity ensures that data remains accurate and unaltered, nonrepudiation provides assurance that someone cannot deny the validity of their actions regarding data, and confidentiality protects data from unauthorized access. However, in the context of backing up data and ensuring its accessibility, availability stands out as the key focus.