The exhibit shows that R1 and R2 use the same IPv4 subnet, 192.168.1.0/24, on separate LAN interfaces. Because these interfaces belong to different Layer 2 segments, the attached PCs cannot communicate directly despite using the same subnet.

Disabling OSPF on R1 ' s GE0/0/1 does not remove its connected 192.168.1.0/24 route. R1 therefore continues treating destinations such as 192.168.1.2 as directly reachable through that interface, making option A false.

If GE0/0/1 fails, however, the connected route is removed. Assuming R2 advertises its LAN prefix into OSPF, R1 can install the route learned through R2 over the inter-router link.

Under that assumption, R1 can reach 192.168.1.2 and 192.168.1.12.

Therefore, B, C, and D are the intended answers. The OSPF advertisement assumption is essential because the exhibit alone does not show the complete protocol configuration.

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