The dialog appears when you click Insert > Web Controls > Parameter Control on the menu bar, drag Parameter Control from the Toolbox panel, or click the down arrow on the Insert Control Objects button 
and select Parameter Control from the drop-down list. It helps you to insert a parameter control into a report for delivering parameter values. See the dialog.
The followings are details about options of this dialog:
Select a Parameter
Lists all the parameters except cascading parameters used in the current report. Specfiy the one you want to use in the parameter control.
OK
Inserts the parameter control into the report and closes the dialog.
Cancel
Cancels the operation and closes the dialog.
Help
Displays the help document about this feature.
