You are troubleshooting a one-way call problem with a Cisco 7920 wireless IP phone on a standalone WLAN. What may have caused this problem？（）

• A、The minimum data rate is not set to 11 Mbps.
• B、Publicly Secure Packet forwarding is enabled.
• C、The access point is set to the least congested channel.
• D、An address resolution protocol has been disabled.