What is the automation step to ensure Cloud Storage bucket accessibility for production photos after promoting a Node.js application?

The correct choice involves adding a build step in the cloudbuild.yaml file using the gsutil cp -r command to ensure that production photos are accessible in the Cloud Storage bucket after deploying the Node.js application. This option is appropriate because gsutil is a command-line tool specifically designed for managing Cloud Storage resources. The cp command allows for recursive copying of files, which is essential for transferring a directory of photos to the bucket efficiently.

Automating this step in the cloudbuild.yaml allows for a seamless update of the production environment without requiring manual intervention. This is particularly important in continuous integration and continuous deployment (CI/CD) workflows, where automation is critical for maintaining speed and reliability in the deployment process.

Additionally, by leveraging the capabilities of Cloud Build, you ensure that every time a new version of the application is deployed, the necessary assets, like photos, are also properly managed and updated in the production environment. This contributes to a smoother user experience, as all resources needed by the application are synchronized and available as required.