多项选择题
A. 228.10.10.7
B. 229.11.10.7
C. 229.138.10.7
D. 229.138.10.8
E. 228.10.10.8
F. 228.10.138.7
多项选择题 Which three IP addresses are valid multicast addresses?（）
单项选择题 What is the purpose of a rendezvous point (RP)?（）
单项选择题 Refer to the exhibit. IP multicast for group address 224.1.1.1 has been enabled on all router s in the network. Hosts on Network A receive the multicast traffic. However, hosts on Network B do not. On the basis of outputs provided, what could be the cause of the problem? （）