What command is used to map internal extensions to the corresponding E.164 PSTN number when using Cisco Unified Communications Manager Express in SRST mode?

What command is used to map internal extensions to the corresponding E.164 PSTN number when
using Cisco Unified Communications Manager Express in SRST mode?

A.
ephone-dn

B.
dialplan-pattern

C.
number

D.
number-e.164

E.
ephone-transnumber