An administrator receives a ticket reporting unwanted traffic between production and development servers.

What makes this a strong certification question is that several answers look technically related, but only one aligns with the exact behavior of Flow networking or Flow security. The correct response is A, meaning “Update the policy to disallow the unwanted traffic.”. The Network Controller supplies the control-plane services required for Flow Virtual Networking. Without it, Prism Central cannot build and manage overlays, gateways, and related virtual networking constructs consistently across the cluster. From a troubleshooting standpoint, the validation path is policy scope first, then categories or identity mapping, then hitlog evidence, service definition, and finally policy precedence. A strong exam habit is to ask which Nutanix construct would have to change for the symptom or requirement to change. That mental shortcut usually separates the real answer from distractors that mention generic networking steps, disruptive resets, or unrelated configuration objects. Notice that B does not fit because it targets a different layer of the Nutanix networking and security stack than the one causing the outcome here. C sounds plausible, but it does not align with the specific Flow policy object or precedence rule that controls this case. The key takeaway is that Flow is intentionally.