Two OSPF neighbor routers are stuck in the EXSTART state. After a while, the neighborship goes
down. A network engineer is debugging the issue when both routers show the OSPF log message
“too many retransmissions.” What is the possible root cause?

A.
OSPF area mismatch

B.
OSPF hello-interval mismatch

C.
interface MTU mismatch

D.
interface network type mismatch