单项选择题
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
多项选择题 Whichtwomulticastaddressrangesareassignedassource-specificmulticastdestinationaddressesandarereservedforusebysource-specificapplicationsandprotocols？（）
单项选择题 Refer to the exhibit. Look at the command output. What would be the most probable reason for this port-ID mismatch？（）
单项选择题 WhichtypeofdomainsisinterconnectedusingMulticastSourceDiscoveryProtocol？（）