A team is preparing a production rollout and needs to avoid a design mistake. Which approach best demonstrates federated queries in a IBM Certified watsonx Data Lakehouse Engineer environment?

The correct answer is option C: Use federation when data should be queried across sources without unnecessary movement.. This aligns with IBM's Data integration patterns guidance, which emphasizes use federation when data should be queried across sources without unnecessary movement as the recommended approach for production deployments. Option A (Federate only after duplicating every source locally) is incorrect because it either bypasses IBM's recommended architecture or introduces operational risk that the correct approach is specifically designed to avoid. Option B (Use federation to avoid all access controls) is incorrect because it either bypasses IBM's recommended architecture or introduces operational risk that the correct approach is specifically designed to avoid. Option D (Assume federation makes slow remote sources local) is incorrect because it either bypasses IBM's recommended architecture or introduces operational risk that the correct approach is specifically designed to avoid. Understanding this distinction is critical for the C9007300 exam: IBM watsonx.data is designed to enforce governance, performance, and operational best practices through its built-in architecture, and the correct answers consistently reflect those architectural constraints rather than shortcut alternatives.