CWNA

Answer - D - Wi-Fi is not compatible with the 802.11a standard.

Key Takeaway: Wi-Fi is a term used to identify the 802.11b wireless Ethernet standard. 802.11b uses the same unregulated radio signaling frequency at 2.4 GHz, at a maximum of 11 Mb/sec. Wi-Fi has a range of approximately 150 feet. Wi-Fi is compatible with 802.11b devices. 802.11a devices use frequencies and modulation techniques that are completely different from that used by 802.11b devices and hence, is not compatible with 802.11b.