Which of the following actions is prohibited for personal protection officers?

The action that is prohibited for personal protection officers is providing personal protection services without an endorsement. In Texas, personal protection officers must have specific endorsements to engage in personal protection activities legally. This requirement ensures that officers are qualified and have received the necessary training to perform their duties safely and effectively. Without this endorsement, an individual cannot legally provide personal protection services, which could lead to legal ramifications for both the officer and the company they represent. This regulation is in place to maintain professional standards within the private security industry and to protect the public.

In contrast, the other options relate to situations that may not necessarily be prohibited in the same way. For example, working for multiple employers or carrying their pocket card typically does not violate regulations as long as it is within the bounds of the law and does not conflict with their duties. Engaging in other regulated services may be allowed as long as it's not in conflict with their primary responsibilities as personal protection officers.