Which of the following statements describe the characteristic of link state routing protocols?（）

• A、The exchange of an advertisement is triggered by a change in the network.
• B、All routers exchange routing tables with each other in a multipoint network.
• C、Packets are routed based upon the shortest path to the destination.
• D、Paths are chosen depending on the cost efficiency factor.
• E、Every router in an OSPF area is capable of representing the entire network topology.
• F、Only the designated router in an OSPF area can represent the entire network topology.