JSFiddle - React, Tailwind, and code Playground
HTML
<select name="cars" multiple>
<option value="Volvo">Volvo</option>
<option value="saab">Saab</option>
<option value="benz">benz</option>
<option value="audi">Audi</option>
</select>
JavaScript
$(function() {
$('select[name="cars"] option[value="saab"], select[name="cars"] option[value="audi"]').attr('selected', 'selected');
});