In Juniper's campus fabric architectures, the location of the Layer 3 gateway (IRB) differentiates between CRB and ERB models:

Centrally-Routed Bridging (CRB): L3 gateways are placed at the core layer.

Edge-Routed Bridging (ERB): L3 gateways are placed at the distribution layer, closer to the edge.

''In the ERB model, Layer 2 gateways are deployed at the access layer, and Layer 3 gateways are deployed at the distribution layer.''

Option A (CRB): Incorrect --- L3 is at the core, not distribution.

Option B (IP Clos): Incorrect --- in 3-stage Clos, L3 is pushed to the access layer.

Option D (EVPN multihoming): Incorrect --- this is about redundancy, not gateway placement.

Option C (ERB): Correct --- L3 gateways sit at the distribution layer in the ERB architecture.

Juniper Mist AI for Wired -- Campus Fabric Architecture Models

Juniper Validated Design -- Core/Distribution CRB vs ERB Gateways

Junos OS EVPN-VXLAN Campus Fabric Deployment Guide