Can we make a page that contains only an extender control?

No, we can't. The extender controls need to have a target control to extend; they don't work alone.

Which property is common to all the AJAX extender controls?

All the Extender controls have a property called TargetControlID, which indicates the control that the extender acts on.

What is the main advantage of using the PopupControlExtender?

The main advantage of the PopupControlExtender is it allows you to hide choices for a control within an UpdatePanel, saving valuable screen space.

Which method of the PopupControlExtender do we need to call to display the results?

We can use The Commit( )method is the method of the PopUpControlExtender that causes the target control to display the results .

What view do we use to set the WatermarkText property in the page ?

From source view, we can set the WatermarkText property, but it's not visisble in the design view.