Which of the following is an interior control used in businesses?

• A. Vents secured with metal grating.
• B. Dropped ceilings with motion sensors inside to counter access through.
• C. Alarmed external cameras outside.
• D. None of the above.

Answer: (A)

Interior security controls are measures used inside a business to prevent or detect unauthorized entry. Securing vents with metal grating creates a solid physical barrier at a vulnerable interior entry point, blocking someone from crawling through the ventilation system to reach interior spaces. This direct, passive barrier makes it a clear interior control. Dropped ceilings with motion sensors inside are an interior measure too, but they function mainly as detection and can be more complex to maintain. Alarmed external cameras outside monitor the outside perimeter, so they’re not interior controls.