What is a vaild match criteria for a firewall filter?（）

A.prefix-list
B.protocol ospf
C.next-term
D.AS path
E.prefix-term

A.Apply an import policy to OSPF; this will import the static routes into OSPF
B.Apply an export policy to protocol "static"; this will export the routes to other protocols.
C.Apply an import policy to the forwarding table; this will import the routes, allowing them to be forwarded to OSPF neighbors.
D.Apply an export policy to OSPF; this will export the static routes to your OSPF neighbors.

A.Import policies concern routes received and determine which routes get put into the routing table.
B.Export policies concern routes received and determine which routes get put into the routing table.
C.Export policies are applied before the routing table.
D.Import polices are applied after the routing table.