public ActionResult <LinkorUnlinkCategory> AddCategoryToQuestion(string id, [FromBody]  LinkorUnlinkCategory linkOrUnlink)
 {
     try
     {
         linkOrUnlink.QuestionId = id;
         _qs.AddCategoryToQuestion(linkOrUnlink);
         return(Ok(linkOrUnlink));
     }
     catch (Exception e)
     {
         return(BadRequest(e.Message));
     }
 }