title: AngularJS disable dropdown option which previously selected
body: <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-js lang-js prettyprint-override"><code>var demoApp = angular.module('myApp', []);
  demoApp.controller('QaController', function($scope, $http) {
      $scope.loopData = [{}, {}];
  
      $scope.questions = {
          model: null,
          availableOptions: [
              {id: '1', name: 'What is your childhood name?'},
              {id: '2', name: "What is your first school?"},
              {id: '3', name: "What is your first job place?"},
              {id: '4', name: "What is your pet name?"}
          ]
      };
  
      $scope.submit = function() {
          $scope.result = $scope.loopData;
      };
  
  });</code></pre>
  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"&gt;&lt;/script&gt;
  
  
  &lt;body ng-app="myApp"&gt;
          &lt;div class="wrapper wrapper-content middlealigen col-sm-12" ng-controller="QaController"&gt;
              &lt;form ng-submit="submit();"&gt;
                  &lt;div ng-repeat="x in loopData"&gt;
                      &lt;h5&gt;Q. {{$index + 1}}&lt;/h5&gt;
                      &lt;select class="form-control" name="question-drop" id="question_dropdown" ng-model="x.question" ng-options="option.id as option.name for option in questions.availableOptions"&gt;
                          &lt;option value=""&gt;Select Question&lt;/option&gt;
                      &lt;/select&gt;
                      &lt;input type="text" placeholder="Enter Answer" name="answer" class="form-control" ng-model="x.answer" /&gt;
                      &lt;div class="m-b"&gt;&lt;/div&gt;
                  &lt;/div&gt;
                  &lt;button type="submit" class="btn btn-primary"&gt;Submit&lt;/button&gt;
              &lt;/form&gt;
  
              &lt;div ng-if="result"&gt;
                  &lt;pre&gt;{{result | json}}&lt;/pre&gt;
              &lt;/div&gt;
  
          &lt;/div&gt;
      &lt;/body&gt;</code></pre>
  </div>
  </div>
  </p>
  
  <p>Can you please check my code snippet. Here is two dropdown.
  If I select <code>What is your childhood name?</code> from  <code>Q. 1</code> dropdown then this option should be disabled in the <code>Q. 2</code> dropdown. How can I do that?</p>