You use Microsoft .NET Framework 4 to create a Windows Presentation Foundation (WPF) application. The application has a window named MainWindow that has a StackPanel control named sp as the root element. <br /> You want to create a Button control that contains a TextBlock control with the "Save" Text property. <br /> You need to create the control dynamically and add the control to sp. <br /> Which code segment should you write in the constructor of the MainWindow class?()
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