Answer: 1. Build a docker image from the Dockerfile and upload it to Container Registry. 2. Create a Deployment YAML file to point to the newly uploaded image. 3. Use the `kubectl` command line utility to create the deployment with that file.

Option A is incorrect because the `gcloud app deploy` command is used for deploying applications to Google App Engine, not for deploying containerized applications to Kubernetes Engine. Option B is incorrect because the `kubectl` tool cannot use an image directly from Cloud Storage; the correct place to upload the docker image is Container Registry. Option C is incorrect because `kubectl app deploy` is not a valid command; the correct command would be `kubectl apply -f`. Option D is correct because it follows the proper steps for dockerizing and deploying the application on Kubernetes Engine: building a docker image from the Dockerfile, uploading it to Container Registry, creating a Deployment YAML file to point to the uploaded image, and then using the `kubectl` command to create the deployment using the YAML file.

Author: LeetQuiz Editorial Team