JSFiddle - React, Tailwind, and code Playground

HTML

<select multiple="true">
    <option value="1">Option 1</option>
    <option value="2">Option 2</option>
    <option value="3">Option 3</option>
    <option value="4">Option 4</option>
</select>

JavaScript

$("select option[value=2]").attr("selected", true);
$("select option[value=4]").attr("selected", true);