how can we selected values in dropdown list through out site in master page

hi friends,


  Hi have requirement like when user select country ,state ,city then we are display selected values in drop down list in all pages.. what he is selected ..In my requirement i put that 3 drop down lists in master .. when we are going to another  page it lost all the selected values how can do this requirement


 please share your idea's 


thanks & regards
venkat 
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