I am not sure what you mean about OptionSet Box. This is why I made some research and it seems that it is used to show a list of predefined options displayed in a drop-down that a user can choose from by checking/unchecking. In this case, I can suggest several controls from Telerik UI for Winforms suite that might be suitable for you:
RadCheckedListBox control - RadCheckedListBox is an enhanced alternative to the standard Windows Forms checked list box control. It displayed a list box in which a checkbox is displayed to the left of each item.
RadListView control - RadListView has built-in checkboxes functionality which can be shown by setting the ShowCheckBoxes property of RadListView to true. You can find more information here.
RadCheckedDropDownList control - RadCheckedDropDownList combines RadDropDownList and RadAutoCompleteBox in order to provide the functionality to check items in the drop-down area and tokenize them in the text area.
Could you please take a look at the suggested controls and consider if any of them should be suitable for you?
Should you have any other questions do not hesitate to ask.
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