These measures are considered deterrent controls because they are intended to signal to potential attackers that the area is monitored or has certain security protocols in place, decreasing the likelihood that someone will attempt a breach or unauthorized access. Warning signs communicate a message of possible consequences or surveillance, while security cameras are a visible reminder of monitoring, both of which can deter malicious activities. In contrast, preventive controls would actually stop an incident from happening, such as a firewall preventing unauthorized network access, which is not the primary function of warning signs or security cameras.