You’re designing a multi-region deployment of your application on OCI.

Goal: Balance global load balancing with regional WAF protection near users.

Option A: Single WAF in one region creates a bottleneck and increases latency—insufficient.

Option B: GLB distributes globally to regional Load Balancers, each with a WAF, ensuringprotection close to users—correct.

Option C: WAF before GLB centralizes protection, adding latency and a single failure point—incorrect.

Option D: Source IP routing with regional WAFs is less optimal than GLB’s health-based routing—less effective.

Conclusion: Option B optimizes both goals.

Oracle states:

"OCI GLB distributes traffic across regions. Pair with regional Load Balancers and WAFs for localized protection and optimal performance."This supports Option B. Reference:Global Load Balancer Overview - Oracle Help Center(docs.oracle.com/en-us/iaas/Content/Balance/Concepts/globalbalance.htm).