The correct answer is: A. CSI is a standard API specification that allows Kubernetes and other orchestrators to use different storage systems via plugins. CSI means Container Storage Interface. It lets storage vendors create plugins/drivers that Kubernetes can use for persistent storage. Typical flow: StorageClass → PersistentVolumeClaim → PersistentVolume → Pod Why not the others? B — that describes networking, not storage. C — CSI is not Kubernetes-only, and CSI drivers are usually external plugins. D — CSI does not automatically provision local storage without drivers/plugins. Answer: A.