JSFiddle - React, Tailwind, and code Playground

HTML

<select name="test1" id="test1">
   <option value="Select">Select</option>
   <option value="a">a</option>
   <option value="b">b</option>
   <option value="c">c</option>
</select>


<select id="test2" name="test2">
<option value="Select">Select</option>
   <option value="a">a</option>
   <option value="a">b</option>
   <option value="a">c</option>
   <option value="b">1</option>
   <option value="b">2</option>
   <option value="b">3</option>
   <option value="c">c</option>
 </select>

JavaScript

jQuery(document).ready(function($){
    var options = $('#test2 option');
    $('#test1').on('change', function(e){
        $('#test2').append(options);
        if($(this).val() != 'Select') {
             $('#test2 option[value!=' + $(this).val() +']').remove();
        } else {
            $('#test2').val('Select');
        }
       
    });
});