Final answer:
A router is the device that enables the consolidation of T-3, DSL, and frame relay WAN access into one modular box, managing data across different network architectures.
Step-by-step explanation:
The device that enables you to consolidate T-3, DSL, and frame relay WAN access into one modular box is a Router. Routers are versatile networking devices that can manage and direct data on a network, providing connectivity between different network architectures like T-3, DSL, and frame relay. These devices are used in various network environments, from small home networks to large enterprise networks, and are integral in facilitating communications and data exchange across the internet and various Wide Area Networks (WAN).