What is the maximum length of any numeric geographic area address in ITU recommendation E.164?

A.
15

B.
18

C.
21

D.
22

E.
25

Explanation:
E.164 defines a general format for international telephone numbers. Plan-conforming numbers are
limited to a maximum of 15 digits. The presentation of numbers is usually prefixed with the
character + (plus sign), indicating that the number includes the international country calling code
(country code), and must typically be prefixed when dialing with the appropriate international call
prefix, which is a trunk code to reach an international circuit from within the country of call
origination.