单项选择题
A.the time required from receipt of the incoming frame， until the frame/packet has been queued for transmission
B.the time taken for a single packet to traverse the physical medium from one end to the other
C.the time taken to place a frame on the physical medium for transport
D.the time spent for a packet to reside in the output queue of a router
单项选择题 WhichQoSmodelmanagestheQoSrequirementsforthenetworkonaper-hopbehavior（PHB）basis？（）
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？（）