What kind of entity can employ security guards on a contractual basis?

The correct answer highlights that private firms and corporations are capable of employing security guards on a contractual basis. This is because businesses often require security services to protect their property, assets, and employees. Security guards can be hired through contracts to provide various services such as monitoring premises, enforcing policies, and managing access control.

Private firms and corporations have the resources and legal rights to negotiate contracts with security providers, enabling them to customize the security services they need based on specific threats or organizational requirements. This arrangement is a common practice in the private sector, allowing businesses to ensure the safety and security of their environments efficiently.

Government organizations and non-profit organizations may also hire security personnel, but the question specifically asks about who can employ them on a contractual basis, a practice that is predominantly found within private firms and corporations due to their commercial nature and security needs. Individuals, depending on their situation, might have limitations in terms of legal authority or resources to engage security services professionally.