AngularJs data bind drop down

I'm new to CouchDB & Angular.js.

I have the following document in CouchDB.

{
"_id": "Ref_Colors",
"_rev": "1-c4c800fa1dcb510915d1c6c81c8c988c",
"Items": ["Red", "Blue", "Green", "Yellow", "White", "Black"]
}

My Controller function is

app.controller('ColorCtrl', function($scope, $http) {
 $http.get('db/Ref_Colors').success(function (data) {
    $scope.Colors = data.Items;
    });
});

In my HTML page

<div> {{Colors}} </div> 

correctly displays ["Red", "Blue", "Green", "Yellow", "White", "Black"].

But if I try to bind this array to a dropdown the dropdown box remains empty!

<select name="SelectedColor" ng-model="SelectedColor" ng-options="c for c in Colors"></select>

Kindly suggest how to properly bind drop down boxes in AngularJs.