It is recommended that you use channels 1-6-11 on a 2.4-GHz WLAN deployment with three or more
APs, because only channels 1 to 11 are available on the 2.4-GHz Cisco ISM band due to the
regulatory domain. Which one of these statements explains why this channel usage is
recommended?

A.
This channel usage is required by the 802.11 standard.

B.
They are the only non-overlapping channels available on the 2.4-GHz ISM band. Channels other
than 1-6-11 overlap each other.

C.
This is the highest channel usage combination available (allowing three different channels to be
used), combining channels that are separated enough on the 2.4-GHz ISM band to avoid cochannel
interference.

D.
The channels are separated 30-MHz away, and the energy radiated by an 802.11b/g device can
only extend up to 25-MHz within the bandwidth of the channels due to regulations.