Which of the following describes the data store used by Kubernetes to hold configuration and cluster state?

• A. Provide DNS for services
• B. Run the Kubelet
• C. Store logs
• D. Store configuration and state data for the cluster

Answer: (D)

The main idea here is where Kubernetes keeps its official record of the cluster. Kubernetes uses a backing store, etcd, to persist all configuration and state for the entire cluster. Everything the API server manages—nodes, pods, services, config maps, secrets, and the desired versus actual state—gets written to this store. It acts as the single source of truth and is kept consistent across the cluster through consensus.

So the option that describes storing configuration and state data for the cluster matches this role precisely. The other choices describe things that are part of the cluster’s operation but are not the data store: a DNS provider is for name resolution, the Kubelet runs on nodes to manage containers, and storing logs is handled by separate logging solutions.