In FortiOS 7.6, firewall policies can be displayed in multiple views to help administrators understand and manage rules more effectively. The difference in ordering between Interface Pair View and By Sequence View is intentional and documented.
Why the policy order is different
Interface Pair View
Groups firewall policies based on the incoming (From) and outgoing (To) interfaces.
Policies are organized under interface pairs such as:
LAN # WAN
WAN # LAN
Within each interface pair, policies may appear reordered compared to the global list.
This view is designed for readability and troubleshooting, not to show execution order.
By Sequence View
Displays firewall policies in their actual evaluation (processing) order.
This is the top-down order FortiGate uses when matching traffic.
It reflects the real rule sequence that determines which policy is hit first.
Why option C is correct
C). Interface Pair View sorts policies based on matching interfaces, while By Sequence View shows the actual processing order of rules.
This statement exactly matches FortiOS behavior as documented in the FortiOS 7.6 Firewall Policy Views section of the Administrator Guide.
Why the other options are incorrect
A: Interface Pair View does not follow traffic logs, and By Sequence View is not based on "rule priority" grouping.
B: FortiGate does not dynamically reorder policies based on traffic patterns.
D: Security levels do not affect policy ordering in Interface Pair View.

With full SSL inspection, FortiGate performs a man-in-the-middle process: it decrypts the HTTPS session, inspects it, then re-encrypts it. To do this, FortiGate presents a substitute certificate to the client, signed by the CA certificate configured in the SSL/SSH inspection profile (for example, Fortinet_CA_SSL or a custom enterprise CA).
Browsers will show certificate warning errors when the issuing CA is not trusted by the client device/browser trust store. This only happens for HTTPS because certificates are used in TLS; HTTP has no certificate exchange, so no warning appears.
Why the other options are incorrect:
A: Allowing invalid server certificates affects whether FortiGate blocks/permits connections to sites with bad certs; it does not fix the client warning about FortiGate's substituted cert.
B: Proxy vs flow inspection mode does not inherently cause certificate warnings; the warning is about trust of the signing CA.
D: Missing extensions is not the typical reason across "any HTTPS website"; the standard reason is the client does not trust the FortiGate inspection CA

According to the FortiOS 7.6 Troubleshooting and Administration guides, the diagnose debug flow command provides a step-by-step trace of how the FortiGate unit processes a packet.
First, the line "find a route: flag=00000000 gw-0.0.0.0 via port2" indicates that during the routing table lookup, the FortiGate matched the destination against its default route (represented by 0.0.0.0) and determined that the egress interface is port2. This confirms that the default gateway for this traffic is reachable via port2 (Statement A).
Second, the debug trace concludes with the messages "policy-2 Is matched, act-drop" and "Denied by forward policy check (policy 2)". This explicitly indicates that the packet successfully matched the criteria for firewall policy ID 2, and the action configured for that policy is set to Deny (Statement D).
Statement B is incorrect because a Reverse Path Forwarding (RPF) failure would be indicated by a specific
"reverse path check fail, drop" message, which is absent here. Statement C is incorrect because the output shows "proto=1", which corresponds to ICMP (Ping) traffic. UDP traffic would be identified as protocol 17.