JSFiddle - React, Tailwind, and code Playground
HTML
<select id="id_here">
<option>aaaa</option>
<option>bbbb</option>
</select>
JavaScript
document.getElementById('id_here').selectedIndex = -1;
<select id="id_here">
<option>aaaa</option>
<option>bbbb</option>
</select>
document.getElementById('id_here').selectedIndex = -1;