Final answer:
The first widely adopted 802.11 specification was 802.11b, which was introduced in 1999 after the original 802.11 standard and offered better data rates and range.
Step-by-step explanation:
The 802.11 specification that was widely adopted first is 802.11b. The Institute of Electrical and Electronics Engineers (IEEE) developed the 802.11 standards for wireless networking, also known as Wi-Fi. The original 802.11 standard was released in 1997, but it was the 802.11b standard, introduced in 1999, that gained widespread adoption due to its improved data rates and better range compared to its predecessors. Following 802.11b, other specifications like 802.11a, 802.11g, and 802.11n were introduced, offering various improvements in aspects such as speed and range.