What do indicators of espionage often include?

The correct choice focuses on unusual travel patterns as a significant indicator of espionage. When individuals associated with sensitive information or operations exhibit atypical travel behaviors—such as traveling to certain foreign countries without a clear professional or personal reason—it may raise suspicions of potential espionage activity. Such patterns can suggest that these individuals are engaging in covert meetings or seeking to connect with foreign agents.

In contrast, increased collaboration typically reflects a positive and healthy work environment and is not necessarily indicative of espionage. Similarly, improved security cultures and enhanced team dynamics signify strides towards strengthening security and team cohesion respectively, rather than pointing toward suspicious activities. Thus, unusual travel patterns stand out as a clear warning sign associated with espionage that requires further scrutiny and investigation.