anchor.diff:            }
         });
   
  +      $(function () {
  +          $("body").on("click", ".multiple_choices_questionnaire_question", function () {
  +              if (this.checked)
  +                  $(this).parents("table").find(".multiple_choices_questionnaire_question").not(this).each(function () {
  +                      this.checked = false;
  +                  });
  +          });
  +          $("form").on("submit", function() {
  +              var isValid = $("table.question").length == $(".multiple_choices_questionnaire_question:checked").length;
  +              if (!isValid)
  +                  alert("Cada pregunta debe tener una respuesta correcta. ¡Revisa tu cuestionario por favor!");
  +              return isValid;
  +          });
  +      });
  +
     </script>
   
   <% end %>
  
positive.code:           </div>
          </template>
        </div>
        <table class="table-hover table-striped table" v-if="!question._destroy">
          <thead>
          <tr>
            <th>#</th>
  
negative.code:               <td>
                  <label>
                    <input type="hidden" value="" :name="'multiple_choices_questionnaire[questions_attributes][' + qindex + '][answers_attributes][' + index + '][correct]'"/>
                    <input type="checkbox" v-model="answer.correct" :name="'multiple_choices_questionnaire[questions_attributes][' + qindex + '][answers_attributes][' + index + '][correct]'"
                      class="multiple_choices_questionnaire_question"/>
                    Correcta
                  </label>
                </td>
  