Which statements describe the routing protocol OSPF? (Choose three.)

A.
It supports VLSM.

B.
It is used to route between autonomous systems.

C.
It confines network instability to one area of the network.

D.
It increases routing overhead on the network.

E.
It allows extensive control of routing updates.

F.
It is simpler to configure than RIP v2.

Explanation:
http://www.9tut.com/ospf-routing-protocol-tutorial
Routing overhead is the amount of information needed to describe the changes in a dynamic
network topology.
All routers in an OSPF area have identical copies of the topology database and the topology
database of one area is hidden from the rest of the areas to reduce routing overhead because
fewer routing updates are sent and smaller routing trees are computed and maintained (allow
extensive control of routing updates and confine network instability to one area of the
network).