As an IT security manager, you've been asked to improve measures to prevent 'tailgating' at your company's secure data center entrance. Which of the following would most effectively deter this type of security breach where an unauthorized person follows an authorized individual into a restricted area?
Implementing an access control vestibule with two-factor authentication on both sets of doors
Installing a sign that warns against the practice of tailgating
Deploying additional video surveillance cameras at the entrance
Placing a turnstile at the entrance that allows entry after badge scanning