The correct answer is D because the image can be directly updated using the kubectl command, and Kubernetes Engine performs a rolling update. This method allows for updating the images, configuration, labels, annotations, and resource limits/requests of the workloads in your clusters without downtime. Rolling updates incrementally replace your resource’s Pods with new ones, which are then scheduled on nodes with available resources.

For example, to update a Deployment from nginx version 1.7.9 to 1.9.1, you would run the following command:

kubectl set image deployment nginx nginx=nginx:1.9.1

This command updates the nginx image of the Deployment’s Pods one at a time.

• Option A is incorrect because creating a new deployment would result in downtime.
• Option B is incorrect because Kubernetes Engine does not work with instance templates and managed instance groups.
• Option C is incorrect because the service does not have a mapping of an image.