The correct option is Controllers implement a declarative reconciliation loop that compares the actual cluster state to the desired state and makes corrections as needed.

Kubernetes controllers continuously watch resources through the API server and run a reconciliation loop that detects drift between the declared manifests and the actual cluster state. When differences are found the controller issues API operations to create update or delete objects so the cluster converges to the declared state. This automated loop is the core of the declarative model and provides self healing behavior.

Controllers act mainly as passive observers that report status to the Kubernetes API server is incorrect because controllers do more than observe and report. They actively reconcile and take actions to bring the cluster toward the desired state.

Controllers directly update manifest files in version control to enforce desired states is incorrect because controllers operate against the Kubernetes API and do not modify your version control system. Source of truth in Git is usually managed by separate GitOps tools rather than in-cluster controllers themselves.

Controllers perform occasional polls and then execute manual fixes when they detect discrepancies is incorrect because controllers perform continuous reconciliation and apply automated corrections. They do not rely on manual intervention to enforce desired state.

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