What defines the 802.11ac standard?

The 802.11ac standard is defined as a WiFi protocol specifically designed for high-speed data transmission. Introduced as an enhancement over its predecessor, 802.11n, 802.11ac significantly increases the maximum throughput by utilizing wider channels, advanced modulation schemes, and multiple antenna technologies (MIMO - Multiple Input Multiple Output). This allows for faster and more efficient transmission of data over wireless networks, making it ideal for high-bandwidth applications such as streaming video, online gaming, and large file transfers.

The other choices present options that do not accurately reflect the characteristics of the 802.11ac standard. For instance, defining it as a slower WiFi standard fails to recognize its advanced capabilities, while labeling it as a wired networking standard or a protocol for analog signals misses the essence of 802.11ac, which is purely focused on wireless networking in the digital realm.