javascript - ng-option is not working when option list is returned from $http service -

i have following code returns me list of offers service in controller

 mosservicefactory.alloffers().then(function (response) {             $scope.offers = response.data.offers;             console.log(json.stringify($scope.offers));  }); 

i using following code in html display list of options in select tag

<select ng-model="offerlist" ng-option="offer.campaignname offer in offers"></select> 

the json response in service (which stored in $scope.offers):

[{         "offerid": "8a1b0cb44e76781e014e767e7b120001",         "campaignname": "instant july offer",         "campaigndescription": "30% discount on apple",         "campaignstartdate": "2015-07-12",         "campaignenddate": "2015-07-22",         "status": "active",         "enrollmentid": "8a1b0cb44e66dba9014e670a0f8c0001",         "discount": "30",         "discountunit": "discount %",         "datecreated": "2015-07-10",         "datemodified": null,         "instantoffid": 1,         "basketofferitemid": null,         "basketofferquantity": 0,         "basketquantity": 0     }, {         "offerid": "8a6804c24e53e4ab014e53fe72770000",         "campaignname": "july2",         "campaigndescription": "weekend offer first 100 customers.",         "campaignstartdate": "2015-07-08",         "campaignenddate": "2015-07-11",         "status": "expired",         "enrollmentid": "8a1b0cb44e4e8e2b014e53333d5d0001",         "discount": "20",         "discountunit": "discount $",         "datecreated": "2015-07-03",         "datemodified": null,         "instantoffid": 0,         "basketofferitemid": null,         "basketofferquantity": 0,         "basketquantity": 0     }, {         "offerid": "8a1b0cb44e61e491014e622088460003",         "campaignname": "weekend discount",         "campaigndescription": "50% discount",         "campaignstartdate": "2015-07-06",         "campaignenddate": "2015-07-07",         "status": "inactive",         "enrollmentid": "8a1b0cb44e61e491014e6207fbaa0001",         "discount": "50",         "discountunit": "discount %",         "datecreated": "2015-07-06",         "datemodified": "2015-07-06",         "instantoffid": 0,         "basketofferitemid": null,         "basketofferquantity": 0,         "basketquantity": 0     }, {         "offerid": "8a1b0cb44e766cd5014e766ed37b0000",         "campaignname": "abc offer",         "campaigndescription": "50% discount on apple",         "campaignstartdate": "2015-07-12",         "campaignenddate": "2015-07-17",         "status": "active",         "enrollmentid": "8a1b0cb44e61e491014e6207fbaa0001",         "discount": "50",         "discountunit": "discount %",         "datecreated": "2015-07-10",         "datemodified": null,         "instantoffid": 1,         "basketofferitemid": null,         "basketofferquantity": 0,         "basketquantity": 0     }] 

its similar plunker http://plnkr.co/edit/fmagnonom9jvuikvnoyu?p=preview

only difference getting list in response.

but somehow, cant see options in html file !

it should ng-options instead of ng-option