Refer to the exhibit.
switch2#
01:22:10: %PM-4-ERR_DISABLE: channel-misconfig error detected on Fa0/20, putting Fa0/20 in error-disable state
01:22:10: %PM-4-ERR_DISABLE: channel-misconfig error detected on Fa0/21, putting Fa0/21 in error-disable state
switch2#show etherchannel summary
!output omitted
Group Port-channel Protocol Ports
------+-------------+-----------+--------------------------------
1 Po1(SD) - Fa0/20(D) Fa0/21(D)
switch1#show etherchannel summary
!output omitted
Group Port-channel Protocol Ports
------+-------------+-----------+--------------------------------
1 Po2(SD) LACP Fa0/20(D)
An engineer is configuring EtherChannel between two switches and notices the console message on switch 2. Based on the output, which option describes the reason for this error?