What should you do?

You recently deployed a new version of an application to App Engine and then discovered a bug in the release. You need to immediately revert to the prior version of the application.

What should you do?
A . Run gcloud app restore.
B . On the App Engine page of the GCP Console, select the application that needs to be reverted and click Revert.
C . On the App Engine Versions page of the GCP Console, route 100% of the traffic to the previous version.
D . Deploy the original version as a separate application. Then go to App Engine settings and split traffic between applications so that the original version serves 100% of the requests.

Answer: D

Explanation:

Reference: https://medium.com/google-cloud/app-engine-project-cleanup-9647296e796a