JSFiddle - React, Tailwind, and code Playground

HTML

<select data-bind="options: components, optionsValue: 'Component', optionsText: 'Component', optionsCaption: 'Choose Component', value: component"></select>
<button data-bind="click: resetselection">Reset</button>

JavaScript

var ViewModel = function() {
    var self = this;
    self.components = ko.observableArray([{"Component":"1234"}, {"Component":"5678"}]);
self.component = ko.observable();
    self.resetselection = function() {
        self.component("");
    }
}
ko.applyBindings(new ViewModel());