JSFiddle - React, Tailwind, and code Playground
HTML
<select name="myselect" id="myselect" >
<option value=''></option>
<option rel='1' value='1A'>1A</option>
<option rel='1' value='1B'>1B</option>
<option rel='2' value='2A'>2A</option>
<option rel='2' value='2B'>2B</option>
<option rel='2' value='2C'>2C</option>
<option rel='3' value='3A'>3A</option>
<option rel='3' value='3B'>3B</option>
<option rel='3' value='3C'>3C</option>
<option rel='3' value='3D'>3D</option>
</select>
<div>
</div>
JavaScript
$("#myselect").clone().appendTo("div").children(':not([rel=3])').remove();