A、EIGRP supports VLSM， route summarization， and routing update authentication.

B、If the feasible successor has a higher advertised distance than the successor route， it becomes the primary route.

C、Passive routes are in the process of being calculated by DUAL.

D、EIGRP exchanges full routing table information with neighboring routers with every update.

E、A query process is used to discover a replacement for a failed route if a feasible successor is not identified from the current routing information.