FortiGate uses the FortiTelemetry protocol to communicate with FortiAnalyzer and other Security Fabric devices to exchange information such as device status, network topology, and security events1. Only the root FortiGate collects network topology information and forwards it to FortiAnalyzer, where it can be viewed and analyzed2. Reference: = Security Fabric - Fortinet Documentation, Fortinet Security Fabric for Securing Digital Innovations

The reason for the command failure when trying to set the protocol to UDP in theconfig system fortiguardis likely that UDP is not a protocol option in this context. The command syntax might be incorrect or the option to set a protocol for FortiGuard updates might not exist in this manner.
So the correct answer is D. udp is not a protocol option.

From the OSPF interface command output, we can conclude that the port3 network has more than one OSPF router because the Neighbor Count is 2, indicating the presence of another OSPF router besides NGFW-1.
Additionally, we can deduce that the interfaces of the OSPF routers match the MTU value configured as
1500, which is necessary for OSPF neighbors to form adjacencies. The MTU mismatch would prevent OSPF from forming a neighbor relationship.
References:
* Fortinet FortiOS Handbook: OSPF Configuration

From the partial OSPF (Open Shortest Path First) configuration output:
B). The router sends grace LSAs before it restarts: This is implied by the command 'set restart-mode graceful-restart'. When OSPF is configured with graceful restart, the router sends grace LSAs (Link State Advertisements) to inform its neighbors that it is restarting, allowing for a seamless transition without recalculating routes.
Fortinet documentation on OSPF configuration clearly states that enabling graceful restart mode allows the router to maintain its adjacencies and routes during a brief restart period.

The access to www.facebook.com is blocked based on the URL Filter configuration. In the exhibit, it shows that the URL "www.facebook.com" is specifically set to "Block" under the URL Filter section1. References := Fortigate: How to configure Web Filter function on Fortigate, Web filter | FortiGate / FortiOS 7.0.2 | Fortinet Document Library, FortiGate HTTPS web URL filtering ... - Fortinet ... - Fortinet Community