The wireless standard 802.11 has matured over the past few years, but only two provisions have been widely adopted. Which two are commonly accepted?

A.
b, g

B.
a, b

C.
a, g

D.
c, d

Explanation:
802.11b enforces a 11 Mbps data rate, 2.4 GHz frequency bands, and
Direct Sequence Spread Spectrum (DSSS). 802.11g was ratified in 2003 to offer
backward compatibility with 802.11b in the same network. It enforces 54 Mbps data
rate, 2.4 GHz frequency band, and OFDM.