The correct answer is A . Policy ID 8 contains the Supervisors user group, so authentication is required for traffic matching that policy. However, policy ID 9 permits traffic to PLC-1 without a user or user-group authentication requirement. Fortinet explains that when an authentication policy is followed by a fall-through policy that does not require authentication , traffic can match the fall-through policy and proceed without generating a login prompt. This is particularly relevant because the default CLI setting is auth-on-demand implicitly. Under the default implicitly behavior, FortiGate does not trigger active authentication when a matching unauthenticated fall-through policy exists. Setting auth-on-demand always, or requiring authentication on all potentially matching policies, changes that behavior. Therefore, HTTPS succeeds without prompting because authentication was not configured on firewall policy ID 9 .