Dropdownlist

 Hi i would like to add from drpdownlist.selecteditem.text into "session"
and i would like to call the selecteditem.text from another page .
i had declared like this 
Source :(added id into session)

  Session["DDL_Topic"] = DDL_Topic.SelectedItem.ToString ();
       Session["DDL_Sub_Topic"] = DDL_Sub_Topic.SelectedItem.ToString ();
Destination:(i would like to call sessin id from this page)

  Label14.Text = "" + Session["DDL_Topic"].ToString();
       Label15.Text = "" + Session["DDL_Sub_Topic"].ToString();
  I am doing this for "Preview" page
After user has selected item from dropdownlist,he would click on preview page
There i should show in (dropdown) text(i.e which user has selected item)

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