The Company wireless network is using 802.11G access points.  Which two statements are true  about these access points？ （）

• A、 It supports eight different data rates.
• B、 It is fully backward compatible with 802.11b
• C、 It provides the same network throughput with 802.11b clients， 802.11g clients， or a mixed  environment where both clients are present.
• D、 It is only compatibly with the 11 Mbps 802.11b transfer rate.
• E、 It has three non-overlapping channels in its channel options.