In which of the following descriptions about DR is correct? (Multiple choice) A. PIM routers become PIM neighbors by exchanging Hello messages. The Hello messages carry the DR priority and the…

In which of the following descriptions about DR is correct? (Multiple choice) A. PIM routers become PIM neighbors by exchanging Hello messages. The Hello messages carry the DR priority and the interface address of the network segment. B. In the shared network segment of the connection group members, the DR is responsible for sending a Register message to the RP. The DR connected to the group members is called the group member- side DR. C. If the multicast source is directly connected to the multicast source, the DR is responsible for sending Join registration messages to the RP. The DR connected to the multicast source is called the source DR. D. If the current DR fails, the PIM neighbor relationship will time out, and a new round of DR election will be triggered between other PIM neighbors.