You follow Option-A while deploying your Mendix app to Mindsphere but you can't see auto-registration page when you click "view" button as described below documentation.
https://developer.mindsphere.io/howto/howto-app-mendix.html
Solution
Auto-Registration will be available when you start new Mendix project with "Mindsphere Starter Application".
You have two option if you didn't start with it.
Notes