JSFiddle - React, Tailwind, and code Playground

HTML

<script src="//ajax.googleapis.com/ajax/libs/mootools/1.5.1/mootools-yui-compressed.js"></script>
<div>
    <select data-bind="options: animais, optionsText: 'nome', optionsValue: 'id'" />
</div>

JavaScript

var Animal = new Class({
    initialize: function(id, nome) {
        var self = this;
        
        self.id = id;
        self.nome = nome;
    }
});

var viewModel = new Class({
    initialize: function(animais) {
        var self = this;
        self.animais = ko.observableArray(animais);
    }
});

ko.applyBindings(new viewModel([
    new Animal(1, "Cachorro"),
    new Animal(2, "Gato"),
    new Animal(3, "Macaco")
]));