AngularJS: ng-options

HTML

<div ng-app="optionsApp" ng-controller="optionsController as vm">
    <select ng-options="p.gender  for p in vm.genderArray" 
            ng-model="vm.selectedPerson">
    </select>
    <p>You selected {{vm.selectedPerson.gender}} 
</div>

JavaScript

var optionsApp = angular.module('optionsApp', []);
optionsApp.controller('optionsController', optionsController);

function optionsController() {
    var vm = this;
    
    vm.selectedPerson = 'Male'
    
    vm.genderArray =  [{gender: "Please select one"},{gender: "Male"},{gender: "Female"},{gender: "Would rather not say"}];
    vm.selectedPerson = '';
}