Which two are best practices when designing a campus Layer 3 infrastructure? (Choose two.)

Summarizing routes from the aggregation layer toward the core layer reduces the routing table size in the core, improving convergence and stability. This aligns with hierarchical design principles. Tuning Cisco Express Forwarding (CEF) load-balancing hash for Equal-Cost Multi-Path (ECMP) routing ensures efficient and balanced traffic distribution across multiple paths, optimizing bandwidth utilization and preventing congestion. Configuring passive-interface on non-transit links is a good practice for routing protocols but not a primary Layer 3 design principle for campus. Implementing security features at the core is too broad; security should be layered throughout the network. Summarizing from the access layer toward the aggregation layer is also a good practice, but the question asks for best practices when designing the campus Layer 3 infrastructure, and the aggregation-to-core summarization has a more significant impact on the overall Layer 3 design.