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"]').children('[value="saab"],[value="audi"]')
                            .attr('selected', 'selected');
});