You are designing a new feature for an existing Windows Forms application by using Microsoft .NET Framework 4. The application contains multiple forms that are loaded into a parent Multiple Document Interface (MDI) form. Your company policy does not allow the use of thirdparty controls. You need to ensure that the new feature meets the following requirements:
* It provides a threedimensional scale model.
* It allows users to change the colors of the model and communicates the color selections back to the application.
* It allows the model to scale, based on the user’s client computer display resolution.
* It is a child form in the MDI application.
What should you do?

A.
?Design the new feature in the existing Windows Forms application as a Windows form. �Add the form as a child form to the MDI window.

B.
?Design the new feature in a new application by using Windows Presentation Foundation (WPF). �Invoke the new WPF application from the existing Windows Forms application.

C.
?Design the new feature in a new Windows Presentation Foundation (WPF) application. �Host the existing application inside the new WPF application by using the WindowsFormsHost class.

D.
?Design the new feature by using a Windows Presentation Foundation (WPF) user control. �Use the ElementHost class to host the WPF user control in the existing Windows Forms application.