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?
Placing a turnstile at the entrance that allows entry after badge scanning
Deploying additional video surveillance cameras at the entrance
Installing a sign that warns against the practice of tailgating
Implementing an access control vestibule with two-factor authentication on both sets of doors