The OSPF configuration shown in the exhibit is using the default priority value of 1 for the interface port1.
This means that FGT_3 will participate in the DR/BDR election process with the other OSPF routers on the same LAN segment. However, this is not desirable because FGT_3 is a new device that needs to be added to the OSPF network without affecting the existing DR/BDR election. Therefore, to make sure FGT_3 will establish OSPF neighbors without affecting the DR/BDR election, the priority value of the interface port1 should be changed to 0. This will prevent FGT_3 from becoming a DR or BDR and allow it to form OSPF adjacencies with the current DR and BDR. Option B shows the correct configuration that changes the priority value to 0. Option A is incorrect because it does not change the priority value. Option C is incorrect because it changes the network type to point-to-point, which is not suitable for a LAN segment with multiple OSPF routers. Option D is incorrect because it changes the area ID to 0.0.0.1, which does not match the area ID of the other OSPF routers on the same LAN segment. References: https://docs.fortinet.com/document/fortigate/7.
0.0/administration-guide/358640/basic-ospf-example