Which of the following types of Wi-Fi standards operates at 5 GHz and can achieve speeds of nearly 7 Gb/s?

The 802.11ac standard is specifically designed to operate efficiently in the 5 GHz frequency band and can support high-speed data transmission, reaching theoretical maximum speeds of up to 7 Gb/s under optimal conditions. It achieves this through advanced technologies such as Multi-User MIMO (MU-MIMO), wider channel bandwidths (up to 160 MHz), and higher-order modulation (256-QAM).

This makes 802.11ac particularly suitable for environments that require high data throughput, such as streaming high-definition video or online gaming. In contrast, other standards listed do not meet the same speed thresholds or operate at different frequency bands. For example, 802.11n works on both 2.4 GHz and 5 GHz but has maximum theoretical speeds lower than 802.11ac, while 802.11g and 802.11b only operate on the 2.4 GHz band and have significantly lower speed capabilities. Thus, the choice of 802.11ac is accurately aligned with the criteria of operating at 5 GHz and achieving nearly 7 Gb/s speeds.