JSFiddle - React, Tailwind, and code Playground
HTML
<select multiple>
<option>Choose Something multiple</option>
<option>1</option>
<option>2</option>
<option>3</option>
</select>
<select>
<option>Choose Something Else</option>
<option>1</option>
<option>2</option>
<option>3</option>
</select>
<input type="button" value="clear" />
JavaScript
$('input[type=button]').click(function(){
$('select').children(':selected').remove();
});