What two documents must security officers carry on their person at all times?

The correct answer identifies the necessary documentation that security officers are required to carry to ensure they are authorized and recognized as professional personnel in their field. A valid and current security guard registration card serves as proof that the individual is officially registered and licensed to work as a security officer in California. This card indicates compliance with state regulations governing security personnel.

Additionally, having a valid identification card is crucial for verification purposes. It helps in confirming the identity of the officer when they interact with the public or authorities. Carrying both documents establishes accountability and professionalism, which are essential characteristics in the security industry.

In contrast, other options include documents that are not specifically mandated for security officers in their daily duties. They may pertain to other professional requirements or personal necessities that do not relate to the legal and operational requirements of a security officer's role.