单项选择题
A.best-effort delivery
B.ingress committed rate （ICR）
C.shaping and policing
D.egress committed rate （ECR）
E.Integrated Services （IntServ）
F.differentiated services （DiffServ）
单项选择题 Refer to the exhibit. The auto discovery qos command was configured on this interface 24 hours prior to the above configuration. Which statement is true about the configuration?（）
单项选择题 Identifythelinkefficiencymechanism？（）
单项选择题 Toprovidequalityofservice（QoS）forvoicetrafficinanIEEE802.1qnetwork，whichclassofservice（CoS）valueshouldbeusedinthe3-bit，userprioritybits（PRI）field？（）