Which of the Following Statements Offers the Best Advice to Follow

Which of the following statements offers the best advice to follow when receiving telephone calls?

A) When answering someone else's phone, give the person's exact whereabouts.
B) When taking messages for others, repeat the spelling of names and verify telephone numbers.
C) Try to get callers off the phone quickly, as important calls may be coming through at the same time.
D) Since callers know who they have called, there is no need to identify yourself when answering your phone.