Which of the following are considered subcomponents of the problem diagnosis step of thetroubleshooting flow？（Choose all that apply.）（）

A.The adjacency table is populated from a router’s ARP cache
B.CEF does not require the first packet of a data flow to be process switched
C.CEF maintains the Forward Information Base and the adjacency table
D.CEF can be enabled with the interface command ip cef
E.The FIB is populated from a router’s IP routing table
F.On most router platforms CEF is enabled by default

A.CEF switching is disabled on the switch
B.The source device and destination device are in different VLANs
C.The VLAN is excluded from the trunk
D.The host is connected to the switch through an IP phone
E.A faulty cable from host to switch or between switches
F.The trunking encapsulation type is inconsistent on the two ends of the link

A.Cisco Express Fonvarding
B.FIB switching
C.Cache switching
D.Optimized switching
E.Process switching
F.Fast switching