Hi Naresh,
What is the datatype of the 'State' prompt?
If you've added this prompt to the where clause of the query, what exactly are you trying to do with the code above?
If your purpose is to just 'print' the values selected by the user in this prompt and if the datatype of the 'State' prompt is 'String', all you need is a formula with this code:
Join({State}, ", ")
-Abhilash