JSFiddle - React, Tailwind, and code Playground

HTML

<select>
    <option class="someclass" selected="selected">asd</option>
    <option>asd</option>
</select>

<select>
    <option class="someclass" selected="selected">asd</option>
    <option>asd</option>
</select>

JavaScript

console.log($("select").find("option:selected").attr("class"));