Refer to the following configuration:$[$huawei$]$interface eth$-$trunk $1[$huawei$-$Eth$-$Trunk$1]$undo portswitchWhich of the following statements about the undo portswitch command are true?A$.$ This command enables a router to support Layer $2$ link aggregation.B$.$ This command enables a Layer $3$ switch to support Layer $3$ link aggregation.C$.$ This command enables a Layer $3$ switch to support Layer $2$ link aggregation.D$.$ This command enables a router to support Layer $3$ link aggregation.