A. The neighbor's advertised distance must be less than or equal to the feasible distance of the current successor.
B. The neighbor's advertised distance must be less than the f easible distance of the current successor.
C. The neighbor's advertised distance must be greater than the feasible distance of the current successor.
D. The neighbor's advertised distance must be equal to the feasible distance of the current successor .
E. The neighbor's advertised distance must be greater than or equal to the feasible distance of the current successor.

A. Internal routers within the backbone area (area 0)
B. Internal routers within the NSSAs
C. Internal routers within the stubby areas
D. ASBRs
E. ABRs
F. DRs and BDRs