Which of the following measures is not advisable in connection with monitoring labor disputes?

Providing armed guards in connection with monitoring labor disputes can escalate tensions and create a hostile environment. It may instill fear among employees rather than promote a sense of security. Opting for non-confrontational and supportive measures is generally more advisable during labor disputes to ensure safety and maintain a peaceful atmosphere.

Changing perimeter-gate padlocks, issuing special passes to non-striking employees, and notifying employees to keep windows rolled up are all proactive measures aimed at enhancing security and managing access during potentially volatile situations. These alternatives focus on maintaining order and protecting personnel without instigating further conflict, which can occur with the presence of armed guards. Therefore, opting for non-aggressive security options reflects best practices in crisis management during labor disputes.