You use Microsoft .NET Framework 4 to create a Windows Presentation Framework (WPF) application.
You plan to create a custom control that contains four text input fields.
Each of the text input fields within the control will contain a label.
You need to ensure that the text input fields within the control can be validated by using a regular expression validator.
Which class should you inherit from?

A.
TextBox

B.
TextElement

C.
UIElement

D.
UserControl