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<div ng-app="myfirstApp" ng-controller="dropdownController">
<p>First dropdown selected item is : {{selectedItem}}</p>
<select ng-model="selectedItem">
<option value="">--Select--</option>
<option ng-repeat="item in items" value="{{item.age}}">{{item.name}}</option>
</select>
<p>Second dropdown selected item is : {{student.currentActivityId}}</p>
<select ng-model="student.currentActivityId" data-ng-options="a.id as a.name group by a.classname for a in myclass">
</select>    
    
</div>