You create a Microsoft Windows Installer file for a Windows Presentation Foundation (WPF) application that requires Microsoft .NET Framework 4. You need to ensure that the installation starts only if .NET Framework 4 is already installed on the computer. What should you do?（）

A. Use a custom action.
B. Set the MinVersion property to .NET Framework 4.
C. Set the Version property of Windows Installer to .NET Framework 4.
D. Set the Version property of the Launch Condition to .NET Framework 4.