Refer to the exhibit. Which statement is true about a voice VLAN？（）

A. Dense mode multicast requires explicit join messages from their members.
B. Dense mode multicast uses a push model to flood traffic throughout the network and then prunes the  unwanted traffic.
C. Sparse mode multicast uses a pull model to send multicast traffic to where it is requested.  
D. Sparse mode uses reverse path forwarding （RPF） to prune off redundant flows.
E. The primary use of sparse mode multicast is for test labs and router performance testing.

A. If a packet is sent to a multicast group address， all members of the multicast group will receive it
B. If a packet is sent to a multicast group address， the multicast frame contains the source multicast  address
C. A router does not have to be a member of a multicast group to receive multicast data.
D. A router does not have to be a member of a multicast group to send to the group.
E. A router must be a member of a multicast group to receive multicast data.
F. A router must be a member of a multicast group to send to the group.

A. Multicast addresses 224.0.1.0 through 238.255.255.255 are called globally scoped addresses. They are used to multicast data between organizations and across the Internet
B. The multicast address 224.0.0.1 is a globally scoped address that has been reserved for the Network  Time Protocol （NTP） by the IANA
C. Multicast addresses 239.0.0.0 through 239.255.255.255 are called limited scope addresses. They are  constrained to a local group or organization
D. Multicast addresses 224.0.0.5 and 224.0.0.6 are limited scoped addresses that have been reserved for  OSPF
E. Multicast addresses 224.0.0.0 through 224.0.0.255 are used for network protocols on local LAN segments. Because they are always transmitted with a Time to Live （TTL） of 1， they are never forwarded  by a router