The suggested answer is A, B.
To route traffic between two VDCs (Virtual Device Contexts), you need to either connect the VDCs to an external Layer 3 device, ensuring they can communicate through an independent intermediary that handles routing (option A), or cross-connect the ports between the VDCs, so communication can occur directly through these connected interfaces (option B). These configurations are necessary because VDCs are isolated from each other by design, and direct traffic routing within the same device is not supported without external connections.