>e. Valid credentials were presented purporting to authorize non-authorized persons
I'm going with this. Deviations can be granted by security to allow "red badges" to pass. They usually require an escort. All the guard has to do is check swipes and if the person's name is on the list and they have an authorized escort, they are granted access. We give red badges access all the time. Outside contractors, maintenance workers. You just have to secure all classified material before access. The weakness, however, is that no one verifies that material has been secured. If the escort is compromised, then the system breaks down.