The most professional way to evaluate this question is to map the symptom to the Nutanix feature responsible for that function rather than reacting to secondary details in the prompt. The correct response is D, meaning “Static routes for remote subnets on the VPC”. A VPN showing an “Up” state confirms tunnel establishment, but it does not guarantee end-to-end reachability. Actual traffic flow still depends on route advertisement or static routing, proper prefixes, and correct MTU considerations. MTU planning matters because encapsulation adds overhead. When overlay, Geneve, VXLAN, or IPSec is present, a path that looks healthy at 1500 bytes can still fragment or drop larger frames unless the underlay and endpoints are sized correctly. Operationally, Flow Virtual Networking should be checked from the control plane outward: gateway health, peering state, route advertisement, ERP coverage, external path, and MTU when encapsulation is involved. 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 A is not appropriate because NAT changes addressing.