According to theFortiSASE 7.6 Administration GuideandFCP - FortiSASE 24/25 Administratorcurriculum, security posture tags (often referred to as ZTNA tags) are the fundamental building blocks for identity-based and posture-based access control.

Multiple Tag Assignment: A single endpoint can be assigned multiple tags at the same time. For example, an endpoint might simultaneously have the tags"OS-Windows-11","AV-Running", and"Corporate-Domain-Joined".

Evaluation Logic: During the policy evaluation process (for both SIA and SPA), FortiSASE or the FortiGate hub considers all tags assigned to the endpoint. Security policies can be configured to use these tags as source criteria. If an administrator defines a policy that requires both "AV-Running" and "Corporate-Domain-Joined," the system evaluates both tags to decide whether to permit the traffic.

Dynamic Nature: Contrary to Option C, these tags are highly dynamic. They are automatically applied or removed in real-time based on the telemetry data sent by theFortiClientto the SASE cloud. If a user disables their antivirus, the "AV-Running" tag is removed immediately, and the endpoint's access is revoked by the next policy evaluation.

Scalability: While the system supports many tags, documentation recommends a baseline of custom tags for optimal performance, though it confirms that multiple tags are standard for reflecting a comprehensive security posture.

Why other options are incorrect:

Option A: This is incorrect because the system does not pick just one tag; it evaluates the collection of tags against the policy's requirements (e.g., matching any or matching all).

Option C: This is incorrect because tags are dynamic and change as soon as the endpoint's status (like vulnerability count or software presence) changes.

Option D: This is incorrect because the architectural advantage of ZTNA is the ability to layer multiple security "checks" (tags) for a single user.