The correct answer is B. inconsistent channel performance . In WLAN RF design, interference is unwanted RF energy in the same or adjacent frequency space that reduces the usable quality of a channel. Cisco defines interference as unwanted RF signals in the same frequency band that can cause degradation or loss of service.
When interference increases, the channel becomes less predictable: clients and APs experience higher contention, more retries, lower modulation rates, reduced throughput, and unstable latency.
Cisco also notes that overlapping channels can create RF interference, leading to connectivity issues and poor throughput. In co-channel interference scenarios, adjacent radios on the same channel interfere with network performance through collisions or excessive CSMA deferrals, degrading WLAN performance. This directly maps to inconsistent channel performance because the channel may appear usable at one moment and congested or impaired the next.
The other answers are not the best operational result. Frame aggregation may be impacted indirectly, but it is not the primary RF-level outcome. Scheduled contention access is not caused by interference. Extended coverage patterns are related to antenna gain, transmit power, and propagation, not high interference.
Reference topic: RF Fundamentals - interference, channel utilization, co-channel interference, adjacent-channel interference, retries, and WLAN performance degradation.

The command that enables web-based client authentication on the WLAN issecurity web-auth. Cisco's Catalyst 9800 Web-Based Authentication guide shows the WLAN configuration workflow: enter WLAN configuration mode, disable WPA security for the open Layer 2 guest WLAN, then "Enable web authentication for WLAN" usingsecurity web-auth. Cisco then applies the authentication list and parameter map withsecurity web-auth authentication-list ...andsecurity web-auth parameter-map ..., which refine the WebAuth method and portal behavior after WebAuth itself is enabled.
Cisco's LDAP authentication example mirrors the exhibit exactly:wlan webauth 2 webauth, removal of WPA
/802.1X Layer 2 security,security web-auth,security web-auth authentication-list ldapauth, andsecurity web- auth parameter-map global. Option B only creates or enters the WLAN profile with WLAN ID 2 and SSID name. Options C and D disable WPA2 and 802.1X AKM; they do not authenticate clients. Reference topics:
Client Connectivity Configuration - guest WLAN authentication, WebAuth, Layer 3 security, authentication lists, parameter maps, and Catalyst 9800 WLAN security configuration.

An RTS frame is an 802.11control frameused in the Request to Send/Clear to Send exchange. Cisco identifies RTS as a Request to Send frame and explains that 802.11 control frames assist in delivering data frames between stations. Cisco further states that the RTS/CTS function is optional, helps reduce collisions when hidden stations are associated to the same access point, and that a station sends an RTS frame as the first phase before transmitting a data frame.
Therefore, option B is correct because the RTS frame requests access to the wireless medium before data transmission. If the receiving station or AP replies with CTS, nearby stations defer transmission based on the duration information, reducing collision probability. This is especially relevant in hidden-node environments where two clients can hear the AP but cannot hear each other. Option A refers to RF spectral-mask compliance, which is a physical-layer regulatory concept. Option C confuses NAV behavior with roaming; RTS/CTS may influence virtual carrier sensing, not client roaming updates. Option D is unrelated because frame compression is not an RTS function. Reference topics:802.11 frame types, control frames, RTS/CTS, CSMA/CA, hidden-node mitigation, and medium reservation.

In Cisco Catalyst Center,device suppressionis the recommended method to prevent unnecessary alerts during planned maintenance windows. By enabling device suppression, the system temporarily suspends monitoring and alert generation for the selected devices while allowing telemetry collection to continue. This ensures that maintenance operations, such as firmware upgrades, configuration changes, or physical mesh AP servicing, do not trigger false-positive alarms. Once the maintenance window concludes, alerts resume automatically, and the engineer can verify that all services are operational and that no critical issues were overlooked.
Disabling telemetry on the WLC (option A) is not advised because it prevents visibility into device health and network performance, potentially causing gaps in monitoring data. Using SWIM (option B) is relevant for automated firmware updates but does not inherently suppress alerts during maintenance. Scheduling maintenance for devices (option C) without enabling device suppression may still generate alerts if the monitoring system detects device reboots or temporary unreachability.
Cisco wireless operational guides specifically highlightdevice suppression as the key tool for managing alerting behaviorduring planned events in mesh or enterprise WLAN deployments, providing a controlled approach to maintenance with minimal disruption to monitoring accuracy. Reference topic:Wireless Monitoring and Management - Catalyst Center, device suppression, scheduled maintenance, and alert control.

WPA2 Personal (PSK) authentication relies on a shared secret (preshared key) configured on both the wireless LAN controller (WLC) and the client device. In the exhibit, the WLAN is configured with WPA2 and PSK (set-key ascii MyKey123), which means the network expects clients to use the same preshared key to authenticate. To enable client connectivity, the preshared key must be manually entered on each client device; this aligns the client and WLC authentication parameters. Options B, C, and D are unrelated to WPA2 Personal: MAC filtering is a security policy mechanism, Active Directory integration supports WPA2 Enterprise with 802.1X authentication, and client certificates are used for certificate-based EAP methods, not PSK. Cisco Wireless Core Technologies emphasize that PSK deployments require consistent key configuration across the WLAN and clients, and that the preshared key is the critical element for successful authentication. This ensures secure, encrypted communication while providing simple setup for small or branch deployments without an enterprise RADIUS infrastructure. Reference topics:Client Connectivity Configuration - WPA2 Personal, preshared key authentication, WLAN configuration, branch deployment WLAN security.