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();