I want to know how to bind dropdownlist using ajax get. This is the code, What is wrong?

 $("#dropdown").on("click",
                function ()
                {
                    $.ajax(
                        {
                            url: '@Url.Action("List", "Employee")',
                            type: "POST",
                            data: $("#dropdown").serialize(),
                            success: function (data) {
                                var org = '<option>Select Organisation </option>';
                                for (var i = 0; i < data.length; i++) {
                                    org += '<option value="' + data[i].organisationid + '">' + 
                                data[i].organisationname + '</option>';
                                }
                                $("#dropdown").html(org);
                            }
                        });