An organization wants its users to validate a series of new features for their app. Why should they use App Engine?

An organization wants its users to validate a series of new features for their app.
Why should they use App Engine?

A. Because their app is containerized and enabled by microservices B. Because the updated app will only include new features C. To run different versions of the app for different users D. To run different versions of the app for the same user