Angular: select (multiple)

HTML

<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.0-rc.2/angular.min.js"></script>
<div ng-controller="MyCtrl">
   <ul>
   <div ng-repeat="data in items">
       <pre>{{data|json}}
       </pre>
    <!--  <select ng-model="data.myChoice" 
     ng-options="key as key for (key , value) in data.choices track by $index">
     <option value="">Select Connection</option>
     </select> -->
     
      <select ng-model="data.myChoice">    
        <option value="">Select Connection</option>
        <option ng-repeat="(key , value) in data.choices track by key" ng-value="key" title="{{key}}"
        >{{key}}</option>
    </select>
   </div>
   
   </ul>
</div>
 ng-options="key as key for (key , value) in data.choices track by data.choices"

JavaScript

var myApp = angular.module('myApp',[]);

function MyCtrl($scope) {
     $scope.items = [
  {
    "title": "1",
    "myChoice" :"",
      "choices": {
        "pizza": {
          "type": 1,
          "arg": "abc"
        },
        "burger": {
          "type": 1,
          "arg": "pqr"
        }
      }
   },
   {
    "title": "2",
     "myChoice" :"",
      "choices": {
        "pizza": {
          "type": 1,
          "arg": "abc"
        },
        "burger": {
          "type": 1,
          "arg": "pqr"
        }
      }
   }
  ];
}