DropdownField 'chosen' settings

Is there a simple way to modify the options on the chosen (Chosen: A jQuery Plugin by Harvest to Tame Unwieldy Select Boxes) portion of a DropdownField?

e.g. I want to set allow_single_deselect:true so it shows the little x icon to clear a single select field.

I have searched but can only see the references in bundle.js and vendor.js but nothing to access these settings from the application side.