You are developing a Windows Presentation Foundation (WPF) application
The application is for commercial use and requires a valid license key to be entered. You create a project type of Class Library code to validate license keys
You need to ensure that the user enters a valid license key during installation of the software.
Which deployment should reference the class library?（）

You are developing a Windows Presentation Foundation (WPF) application.
You are implementing a test strategy for the application.
You need to ensure that the test class can repeat user input.
From which base class should the test class inherit?（）