Using new backup router in spite of faulty one in ospf domain but relationship with neighbor in one interface only not working , what is the reason of this problem?

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#1

Using new backup router in spite of faulty one in ospf domain but relationship with neighbor in one interface
only not working , what is the reason of this problem? (Choose 2)
A. area Id mismatch
B. authentication mismatch
C. process id of ospf not match
D. ospf timers not match

Correct Answer: AD