D (RollingUpdate) is correct. In Kubernetes, the Deployment resource’s default update strategy is RollingUpdate, which replaces Pods gradually rather than all at once. This supports zero-downtime updates when the workload is properly configured (sufficient replicas, correct readiness probes, and appropriate maxUnavailable / maxSurge settings). As new Pods come up and become Ready, old Pods are terminated in a controlled way, keeping the service available throughout the rollout.

RollingUpdate’s “zero downtime” is achieved by maintaining capacity while transitioning between versions. For example, with multiple replicas, Kubernetes can create new Pods, wait for readiness, then scale down old Pods, ensuring traffic continues to flow to healthy instances. Readiness probes are critical: they prevent traffic from being routed to a Pod until it’s actually ready to serve.

Why other options are not the Kubernetes-native “strategy” answer here:

Recreate (B) explicitly stops old Pods before starting new ones, causing downtime for most services.

Canary (A) and BlueGreen (C) are real deployment patterns, but in “Kubernetes-native deployment strategy” terms, the built-in Deployment strategies are RollingUpdate and Recreate. Canary/BlueGreen typically require additional tooling/controllers (service mesh, ingress controller features, or progressive delivery operators) to manage traffic shifting between versions.

So, for a Kubernetes-native strategy that supports zero-downtime updates, the correct and verified choice is RollingUpdate (D).

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