An OSPF adjacency is not forming between two routers directly connected using Ethernet. What are three reasons for this behavior? (Choose three.)
A. The physical connection is down.
B. The IP subnets on both routers are different.
C. The subnet masks on both routers are the same.
D. The network type on both routers is point-to-point.
E. The area numbers on both routers are different.