Fill DropDownList with Json result from Controller using jQuery getJSON in ASP.Net MVC

I have popup form that called dropdown from controller that contain Json data, but i always get empty value for text.

The goal is post the id to context

I have someone can help for this one

public class DataController : Controller
{
    private readonly ApplicationDbContext _context;
    public DataController(ApplicationDbContext context)
    {
        _context = context;
    }
    public JsonResult GetDepartement()
    {
        List<IdTextPair> result = (
            from m in _context.Departements
            orderby m.DepertementId
            select new IdTextPair()
            {
                Id = m.DepertementId,
                Text = m.DepartementName
            }).ToList();
        return Json(new { data = result });
    }
}

@Html.DropDownList("DepartementName", new SelectList(string.Empty, "Id", "Text"), "Please select..", new { @class = "form-control",style = "width:350px;"})
@Html.ValidationMessageFor(a=>a.DepartmentId)

$.getJSON('/Data/GetDepartement', null, function (data) {
    $.each(data, function (index, obj) {
        $('#DepartementName').append('<option value=' +
            obj.id + '>' + obj.text + '</option>');
    });
});