Populate select box

Populate select box

Hello everybody,

I am trying to populate a select box with the help of jquery php and mysql.
Goal is to let the user select a province which then returns a select box with coresponding cities.

Now I am stuck. Here is what I am doing:

On select of province I pass the name via jquery to a php script that queries the db and from there on I am lost. I am able to alert the data via alert($data); But how could I now populate the select field?

Here is the code I am using:

         function load_area($id){
            $.ajax({
                 type: \'POST\',
                 url: \'/subapp_inserate/act_search_box.php\',
                 data: \'pid=\'+$id,
                 success: function(data){
                    //alert whatever PHP script outputs
                      alert(data);
                 }
             });
         }


Thank you for any hint you might have.

Merlin