Which of the following layers in the OSI model cannot be protected by using traditional firewalls?

• Application layer
• Data link layer
• Physical layer
• Presentation layer

Which of the following fire suppression systems is used to suppress a fire at the initial stage using a suppressant agent but it cannot be used in case of a fire covering a large area?

• Standpipe system
• Fire extinguisher
• Sprinkler system
• Pre-piped water system

Which of the following physical security systems allows only one person inside and requests an identity; if the identity is invalid, the person is held inside until a security professional arrives?

• X-ray inspection systems
• Mantrap systems
• Walkthrough detectors
• Metal detectors