问题：

[单选] You develop a Web control. The Web control consists of labels and associated text boxes.You need to ensure that the Web control has both toolbox and visual designer support. What should you do?（）

A . Add a Web Control Library project to your solution. Define a class that inherits from CompositeControl.
B . Add a Windows Control Library project to your solution. Define a class that inherits from UserControl.
C . Add a Web User Control to your project. Define a class that inherits from UserControl.
D . Add a Mobile Web User Control to your project. Define a class that inherits from MobileUserControl.