Crystal Reports using values from dropdown parameter in c

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     hi,

    i'm new to crystal reports.

i want to use a value from a prompting dropdown parameter field,which will have multiple values,  in my query in command editor. but i can't get a parameter with multiple values to use it in the query. 

Is it possible in crystal reports XI  to get a value from a drop down list parameter field and use it in the query. 

I'm using Crystal Reports XI Release 2

please help me on this.Thanks in advance.