Your network contains an Active Directory domain named contoso.com. All servers run Windows
Server 2012. Client computers run either Windows 7 or Windows 8. All of the client computers have an application named App1 installed. The domain contains a
Group Policy object (GPO) named GPO1 that is applied to all of the client computers. You need to add a system variable named App1Data to all of the client
computers. Which Group Policy preference should you configure?
1. Services
2. Ini Files
3. Environment
4. Data Sources
Answer: Pending
Correct answer is 3. Environment.
Environment Variable preference items allow you to create, update, replace, and delete user and system environment variables or semicolon-delimited segments of the PATH variable.
https://technet.microsoft.com/en-us/library/cc772047.aspx