A.CreateandconfigureSMTPconnectorsbetweentheroutinggroups.Donotcreateadditionalconnectorsbetweentheroutinggroups
B.Createandconfigureroutinggroupconnectorsbetweentheroutinggroups.Donotcreateadditionalconnectorsbetweenroutinggroups
C.Createandconfigurelow-costgroupconnectorsandhigh-costSMTPconnectorsbetweentheroutinggroups
D.Createandconfigurehigh-costroutinggroupconnectorsandlow-costSMTPconnectorsbetweentheroutinggroups
参考答案：BC
