to work?

Which line in the following OSPF configuration will not be required for MD5 authentication

to work?

interface GigabitEthernet0/1

ip address 192.168.10.1 255.255.255.0

ip ospf authentication message-digest

ip ospf message-digest-key 1 md5 CCNA

!

router ospf 65000

router-id 192.168.10.1

area 20 authentication message-digest

network 10.1.1.0 0.0.0.255 area 10

network 192.168.10.0 0.0.0.255 area 0

!
A . ip ospf authentication message-digest
B . network 192.168.10.0 0.0.0.255 area 0
C . area 20 authentication message-digest
D . ip ospf message-digest-key 1 md5 CCNA