Which of the following behaviors is most indicative of a potential espionage agent?

The behavior that most strongly indicates a potential espionage agent is a breach of protocol when handling classified information. This action is critical because proper handling of classified materials is fundamental to national security and the protection of sensitive information. A breach of these protocols can signify not only negligence but a willful disregard for established security measures, which is a common characteristic of individuals engaged in espionage activities.

Espionage agents typically seek to access classified information unlawfully, and any deviation from accepted procedures could facilitate that goal. By not adhering to protocol, an individual may expose sensitive data to unauthorized access or may be testing the vulnerabilities in security systems as part of their espionage efforts. In contrast, the other behaviors listed, while possibly concerning, do not directly correlate with active measures taken to compromise information security in the same way a breach of protocol does.