5. Which of the following is correct about direct inward dialing (DID)?

A. Its a feature offered by telephone service providers

B. It allows a direct call to a PBX station instead of going through an auto attendant.

C. A stations DID number could be totally unrelated to its local extension number

D. All of the above

6. For the purpose of traditional 911 emergency service, the early calling line identification (CLID) indicates a pyshical address without ambiguity when.

A. a single family home is the destination

B. A large corporation occupies dozens of floors in a skyscraper, all with the same physical address and general phone number

C. A campus terminates phone lines in a PBX room, with extensions in many geographically separated buildings

D. a multitenant residential building that is poorly managed, with customer names and apartment number mixed up and hidden behind a shared demarcation point