Which of the following is considered a physical security control?

Physical security controls are measures designed to protect the physical assets of an organization, including facilities, equipment, and personnel. Locks and surveillance systems serve this purpose by providing both access control and monitoring capabilities. Locks prevent unauthorized access to buildings or secure areas, while surveillance systems, such as cameras, allow for the monitoring of activities within and around those areas to deter and detect potential security breaches.

In contrast, firewall configurations and data encryption software fall under the realm of logical or technical security controls, which protect data and networks from unauthorized access and threats in the digital space. Intrusion detection systems also serve as a logical control, focusing on identifying and responding to security breaches in network traffic, rather than protecting physical assets directly. Thus, locks and surveillance systems are the only option among the choices provided that are specifically focused on the physical protection of organizational resources.