Access control involves using a combined strategy of

• A. Mechanical systems
• B. Physical barriers
• C. Surveillance
• D. Passwords

Answer: (A)

Access control is about regulating who may enter a space and when, using a layered setup at the entry point. The most concrete, actionable part of that setup is the mechanical systems—locks, strikes, door hardware, and the mechanisms that physically permit or prevent passage. These components translate an authorization decision into action, releasing a door for an authorized user or keeping it secured for others. Without reliable mechanical systems, even strong credentials or vigilant monitoring can’t stop entry at the door itself, because there’s nothing tangible enforcing the rule at the point of entry. A combined strategy uses these hardware elements alongside barriers, monitoring, and credentialing to create effective protection, but the essential enforcement at the entry is delivered by the mechanical systems.