parameter setting

Hello,

I have a SSRS 2012 report with a parameter @Rng.  I'm setting the multi parameter with a simple query for the RANGE values. When the report is run parameters default to ALL or the user can re-run the report with their own selection in the parameter drop list. All is working well...

Is there any way to Add a "Preference Ranges" parameter to my drop list?  I would add the text "Preference Range" to my RangeDropList with a simple union to the existing query. 

The problem I'm having is setting the parameter to a handful of RANGE values when the user selects the "Preference Ranges" from the parameter drop list.  I'm not sure if an expression could be used to solve my issue. 

Any information would be greatly appreciated.

Thanks,

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