Final answer:
Users who will carry out User Acceptance Testing need to have a valid Visual Studio subscription or access to a Visual Studio license.
Step-by-step explanation:
When conducting User Acceptance Testing for the software developed by Proseware Inc, the users who will carry out the testing will need to have the appropriate licensing requirements. Since the completed application is running on software licensed under a Visual Studio subscription for development and testing purposes, the users will also need to have a valid Visual Studio subscription or access to a Visual Studio license. This will ensure that they have the necessary rights and permissions to review and test the application.