The correct answer is C (Platform Engineers). In modern DevOps and platform operating models, platform engineering teams build and maintain the shared delivery capabilities that product/application teams use to ship software safely and quickly. This includes CI/CD pipeline templates, standardized build and test automation, artifact management (registries), deployment tooling (Helm/Kustomize/GitOps), secrets management patterns, policy guardrails, and paved-road workflows that reduce cognitive load for developers.
While application developers (B) write the application code and often contribute pipeline steps for their service, the “build, automate, and offer tooling for developer teams” responsibility maps directly to platform engineering: they provide the internal platform that turns Kubernetes and cloud services into a consumable product. This is especially common in Kubernetes-based organizations where you want consistent deployment standards, repeatable security checks, and uniform observability.
Cluster operators (D) typically focus on the health and lifecycle of the Kubernetes clusters themselves: upgrades, node pools, networking, storage, cluster security posture, and control plane reliability. They may work closely with platform engineers, but “continuous delivery tools for developer teams” is broader than cluster operations. Application users (A) are consumers of the software, not builders of delivery tooling.
In cloud-native application delivery, this division of labor is important: platform engineers enable higher velocity with safety by automating the software supply chain—builds, tests, scans, deploys, progressive delivery, and rollback. Kubernetes provides the runtime substrate, but the platform team makes it easy and safe for developers to use it repeatedly and consistently across many services.
Therefore, Platform Engineers (C) is the verified correct choice.
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