An example of a Security Anomaly is:

A security anomaly represents an unusual or unexpected behavior that could indicate a potential security threat or breach. In this context, unauthorized access to secured files is a clear example of a security anomaly, as it suggests that someone is accessing information that they should not have permission to view, indicating a potential breach of security protocols.

On the other hand, an adversary using technical countermeasures against U.S. intercept technology (such as employing tactics to evade surveillance or detection) also qualifies as a security anomaly. This behavior demonstrates an unexpected action that deviates from standard operational norms, indicating a proactive and possibly advanced approach by adversaries to undermine security measures.

Choosing the option that includes both scenarios correctly identifies that both represent forms of security anomalies. Each highlights different aspects of security breaches, reinforcing the importance of recognizing varied threats in a comprehensive security environment.