JSFiddle - React, Tailwind, and code Playground
HTML
<select class="soma1">
<option>item1</option>
<option>item2</option>
<option>item3</option>
<option>item4</option>
</select>
<select class="soma2">
<option disabled selected>Select</option>
<option>item1</option>
<option>item2</option>
<option>item3</option>
<option>item4</option>
</select>
JavaScript
$(document).ready(function(){
var default_values = $('.soma2').children();
$('.soma1').change(function () {
var cm = $('.soma1').val();
$('.soma2').html(default_values);
$('.soma2').children().each(function(index, element) {
// loop each children and compare
if($(element).text() == cm) {
$(this).remove();
}
});
$('.soma2').prop('selectedIndex', 0); // reset selected value
});
});