Which cmdlet sequence should your application use?

You are designing a custom application to automate the deployment of SharePoint 2010 solutions.
You need to ensure that the application uses Windows Power Shell cmdlets.
Which cmdlet sequence should your application use?

A.
Add-SPSolution, then Install-SPSolution.

B.
Add-SPUserSolution, then Install-SPUserSolution.

C.
Install-SPSolution, then Add-SPSolution.

D.
Install-SPUserSolution, then Add-SPUserSolution.