You want to move the Dataverse solution from your development to the test environment. 
What are the three steps before you export the solution in the Power Apps portal?

Answer options:

A.Export as Unmanaged
B.Publish all changes
C.Convert from Unmanaged to Managed
D.Export as Managed
E.Check for issues
F.Convert from Managed to Unmanaged

Correct Answers: B, D and E 
The solution is a container that can include various components, like tables, fields, apps, site maps, flows, etc.
These components are extensions or/and modifications of the Dataverse database. Developers can create these extensions, package them, and distribute them as solutions. Solutions are distributed as a zip file and can be imported into different environments. There are two types of solutions: unmanaged and managed.
Unmanaged solutions are modifications that developers create in the development environment. When they are ready to test or deploy, they export and import the solution into a test or production environment as managed. Developers cannot change the managed solution. 
When you are ready to test or deploy your solution, you need to Publish all modifications or changes (Number 1) in your solution. Then you should run the Solution checker to check the solution for potential issues. If there are no problems found, you can push the Export button on the top toolbar (Number 2). Power Apps portal opens a new Export blade and reminds you to Publish all changes (Number 1) and Check for the issues (Number 3). And on the next screen, you need to select the type of your export solution: managed or unmanaged. If you are moving your solution to the test or deployment environment, you choose the Export as Managed (Number 4) and push the Export button. 
Power Apps portal creates a zip file with the name of the solution, version number, and adds the word “managed” at the end of the name for the managed solution, like NorthwindTraders_1_0_0_7_managed.zip. 

The Power Platform solution is a mechanism of Application lifecycle management (ALM) implementation by distributing the components for Power Apps, Power Automate, and Dataverse between environments using import and export. 
All other options are incorrect. 
For more information about Power Platform solutions, please visit the below URLs: 

https://docs.microsoft.com/en-us/powerapps/maker/data-platform/solutions-overview
https://docs.microsoft.com/en-us/powerapps/maker/data-platform/import-update-export-solutions
https://docs.microsoft.com/en-us/powerapps/maker/data-platform/export-solutions