Refer to the Exhibit

Refer to the exhibit. Based on the information, what is the purpose of using [Time Source] for authorization?

A) to check how long it has been since the last login authentication
B) to check whether the guest account expired
C) to check whether the MAC address is in the MAC Caching repository
D) to check whether the MAC address status is known in the endpoints table
E) to check whether the MAC address status is unknown in the endpoints table