Which configuration command on D1 (with a similar command on D2) will provide an immediate solution

exhibit The company and the company network have both been growing rapidly. Multiple adds, moves and changes have been applied to the network. Your boss has asked you to troubleshoot a recent OSPF synchronization problem that has arisen. There have been synchronization problems at separate locations in the OSPF area 0. There have been reported link failures during the rapid growth of the company network. You are required to resolve the OSPF problem. OSPF must be able to converge when the network changes.

Which configuration command on D1 (with a similar command on D2) will provide an immediate solution to the missing route problem?

A.
no area 16 stub

B.
no area 16 authentication message-digest

C.
area 16 virtual-link 8.187.175.82

D.
area 16 virtual-link 172.16.4.2

E.
no area 16 stub no-summary

F.
network 172.16.0.0.0.0.255.255 area 16

G.
None of the above

Explanation:
To fix this problem immediately without changing the topology we need to create virtual link between D1 & D2. If you are still confused how to use the virtual link, check out the IPv6 OSPF Virtual Link Sim article.