JSFiddle - React, Tailwind, and code Playground

HTML

<div ng-app ng-controller="TestController">
    <div>
        <label>Organization type:</label>
        <select ng-model="curOrgType" ng-options="o.name for o in orgTypes" ng-change="curOrgSubType = curOrgType.subtypes[0]"></select>
        <span>{{curOrgType.name}}</span>
    </div>
    <div>
        <label>Organization sub type:</label>
        <select ng-model="curOrgSubType" ng-options="o.name for o in curOrgType.subtypes"></select>
        <span>{{curOrgSubType.name}}</span>
    </div>
</div>

JavaScript

function TestController($scope) {
    $scope.orgTypes = [
        {
            id: 1,
            name: 'org1',
            subtypes: [
                {id: 1, name: 'subType1'},
                {id: 2, name: 'subType2'},
                {id: 3, name: 'subType3'}
            ]
        },
        {
            id: 2,
            name: 'org2',
            subtypes: [
                {id: 4, name: 'subType4'},
                {id: 5, name: 'subType5'},
                {id: 6, name: 'subType6'},
                {id: 7, name: 'subType7'}
            ]
        }
    ];
    $scope.curOrgType = $scope.orgTypes[0];
    $scope.curOrgSubType = $scope.curOrgType.subtypes[0];
}