Final answer:
The type of cordless phone that is most likely to interfere with a wireless LAN (WLAN) is 2.4 GHz, while 5.8 GHz and DECT cordless phones are less likely to cause interference. Analog cordless phones can also potentially interfere with WLANs.
Step-by-step explanation:
The type of cordless phone that is most likely to interfere with a wireless LAN (WLAN) is 2.4 GHz. WLANs operate at the 2.4 GHz frequency band, which is also used by older cordless phones. The signal from the cordless phone can interfere with the WLAN signal and cause disruptions or slow down the network performance.
On the other hand, 5.8 GHz cordless phones operate in a different frequency band that usually doesn't interfere with WLANs. DECT (Digital Enhanced Cordless Telecommunications) cordless phones use a different technology and frequency band compared to WLANs, so they are also less likely to cause interference.
Analog cordless phones, which operate using analog signals, can potentially interfere with WLANs as well.