What is a Kubernetes namespace?

Correct answer: A virtual cluster within a physical cluster

Option C is correct because a Kubernetes namespace is a logical partition within a single cluster that provides scope for resource names, enabling multiple teams or environments to share the same physical cluster with isolated resource visibility and access controls. Option A is incorrect because namespaces are not network interfaces; pod networking is handled by CNI plugins and network policies, which can reference namespaces but are not themselves namespaces. Option B is incorrect because container runtimes such as containerd or CRI-O are components of the node infrastructure, not namespace objects in the Kubernetes API. Option D is incorrect because storage volumes are represented by PersistentVolume and PersistentVolumeClaim objects, which are separate from the namespace construct.