A.it is used for load balancing in bidirectional PIM
B.it is used for redundancy in bidirectional PIM
C.it is used for redundancy in PIM-SM
D.it is used for load balancing in PIM-SM

A. UDLD  （UniDirectional Link Detection）
B. spanning-tree loopguard
C. VTP mode transparent
D. switchport mode desirable

A.Membership Query
B.Membership Report
C.Membership Delay
D.Backward Compatible IGMPv1 Report Message

A.Source Specific Multicast and IGMPv2
B.Announcing multicast sources to BGP speakers
C.Anycast RP
D.Intradomain multicast routing

A. Users in SW1 can ping SW2 but not vice versa.
B. Users in SW2 can ping SW1 but not vice versa.
C. Users in SW1 and SW2 can ping each other.
D. Users in SW1 and SW2 cannot ping each other.

A.to prevent multicast packets from looping
B.to prevent PIM packets from looping
C.to instruct PIM where to send a （*， G） or （S， G） join message
D.to prevent multicast packets from looping and to instruct PIM where to send a （*， G） or （S， G） joinmessage

A.232.0.0.0/8
B.239.0.0.0/8
C.232.0.0.0/4
D.FF3x：：/32
E.FF2x：：/32
F.FF3x：：/16

A. spanning-tree misconfiguration
B. speed mismatch configuration
C. cabling problem
D. configuration problem

A.PIM-SM
B.PIM-DM
C.PIM-SSM
D.DVMRP

A. Incorrect VTP domain
B. Incorrect VTP password
C. Incorrect VTP mode
D. Incorrect VTP configuration revision

A. Clear the MAC address table in the switch.
B. Clear the ARP cache in the switch.
C. Clear the ARP cache in the end devices.
D. Clear the ARP cache in the application servers.