What is the difference between 802.11a and 802.11b, and why did 802.11b achieve broader market adoption despite being slower?

• A.802.11a operates at 5 GHz with up to 54 Mbps; 802.11b operates at 2.4 GHz with up to 11 Mbps; 802.11b achieved broader adoption because 2.4 GHz hardware was less expensive to produce due to existing unlicensed band infrastructure and the 2.4 GHz components were cheaper than 5 GHz components at the time
• B.802.11b is faster at 54 Mbps; 802.11a is limited to 11 Mbps
• C.802.11a achieved broader adoption because 5 GHz has less interference, because 802.11n introduced OFDMA, letting one transmission serve many clients at once. An evil twin attack requires physical access to the legitimate AP's console
• D.802.11a and 802.11b are identical; both operate at 2.4 GHz