What are two purposes of the 224.0.1.40 address in Auto-RP?（）

• A、Configured mapping agents listen to this address.
• B、Mapping agents select RP for a group based on highest IP address of all the group's C-RPs.
• C、RP mapping agent advertises complete list of group-to-RP mappings.
• D、All configured PIM-SM routers listen to this address and learn the correct RP to use for each known group.