In Cisco IOS and Cisco IOS XE Software images, when redistributing routes from other routing protocols into OSPF, what is a common reason why some of the routes might not be redistributed into OSPF?

A.	The OSPF external metric type (E1 or E2) is not defined.
B.	The OSPF seed metric is not defined.
C.	The OSPF level (Level 1, Level 2, or Level-1-2) to which the routes will be redistributed into is not defined.
D.	The subnets option in the redistribute command is missing.