JSFiddle - React, Tailwind, and code Playground
HTML
<select id="sel1">
<option>1</option>
<option>2</option>
<option>3</option>
</select>
<select id="sel2">
<option>1</option>
<option>2</option>
<option>3</option>
</select>
JavaScript
$(document).ready(function(){
$("#sel2").html($("#sel1").html());
});