Cisco recommends a decibel referenced to 1 milliwatt signal level for the coverage cell edge at the predetermined data rate that is needed to support the VoWLAN device and call capacity requirements. What is that signal level value for Cisco Unified Wireless IP Phones 7920, 7921G, and 7925G?

A.
-65 dBm

B.
-67 dBm

C.
-69 dBm

D.
-70 dBm