All exam questions require you to select a single answer from the given choices. The following multiple-choice question requires you to select a single, correct answer. Following the question is a brief summary of each potential answer and why it is either right or wrong. You will be tasked with selecting the most correct answer. In some cases, more than one answer might appear correct; you must determine which one is most correct.
Answer: B. Locks are the most commonly used device to control physical access. Locks have been used since the time of the Egyptians. Answer A is incorrect because chains are not the most commonly used devices for physical access control. Answer C is incorrect because alarms don't prevent access; they only inform you that possible unauthorized access has occurred. Answer D is incorrect because a firewall is used to control logical access.