Update <select> via AJAX sucess : I have some DropdownLists in my View

Here is code

     @Html.DropDownList("Question1", null, "Вопрос 1", htmlAttributes: new {@class = "form-control", @style = "height:40px;margin-bottom: 20px;"})


I have AJAX call to add question

Here is code

    <script>
    $(document).ready(function () {
        $('#save_quest').click(function () {
           savequestion();
          });
    });

    // Сохранение вопроса в модальном окне
    function savequestion() {
        $.ajax({
            type: 'Post',
            dataType: 'Json',
            data: {
                Question_new: $('#question').val(),
                Answer: $('#answer').val(),
                Preparing: $('#prepare').val(),
                Retries: $('#retries').val(),
            },
            url: '@Url.Action("CreateNewQuestion", "Questions")',
            success: function (da) {
                if (da.Result === "Success") {
                    $('#myModal').hide();
                    emails_update();
                    } else {
                    alert('Error' + da.Message);
                }
            },
            error: function (da) {
                alert('Error');
            }
        });
    }
</script>


How I can update DropDownList on sucess?

Thank's for help