Which of the following describes unauthorized modification of information?

The correct answer focuses on integrity breach, which refers to the unauthorized alteration of information. Integrity is a crucial pillar of information security, alongside confidentiality and availability. When information is modified without proper authorization, its accuracy and reliability are compromised, leading to a breach of integrity.

This can have significant consequences, as the altered information may produce misleading results or enable malicious activities. Maintaining integrity ensures that data remains accurate, consistent, and trustworthy throughout its lifecycle. Thus, any unauthorized modification directly challenges this core principle of data management and security.

In contrast, the other options pertain to different aspects of information security. Availability relates to ensuring that information is accessible when needed. Confidentiality loss concerns unauthorized access to sensitive information, compromising privacy. Authentication failure deals with the inability to verify the identity of individuals trying to access systems or data. Each of these is important, but they do not primarily address the specific issue of unauthorized modification of information like integrity breach does.