JSFiddle - React, Tailwind, and code Playground

HTML

<h3> Table 1</h3>

<table id="table1" border="1">
     <tr>
         <td>select any option</td>
         <td>
          
   <select>
       <option value="--select--">--select--</option>
  <option value="volvo">Volvo</option>
  <option value="saab">Saab</option>
  <option value="vw">VW</option>
  <option value="audi" >Audi</option>
</select>
         </td>
     </tr>
          <tr>
         <td>select any option</td>
         <td>
          
   <select>
        <option value="--select--">--select--</option>
  <option value="volvo">Volvo</option>
  <option value="saab">Saab</option>
  <option value="vw">VW</option>
  <option value="audi" >Audi</option>
</select>
         </td>
     </tr>
          <tr>
         <td>select any option</td>
         <td>
          
   <select>
        <option value="--select--">--select--</option>
  <option value="volvo">Volvo</option>
  <option value="saab">Saab</option>
  <option value="vw">VW</option>
  <option value="audi" >Audi</option>
</select>
         </td>
     </tr>
</table>
<br>
    
    <h3> Table 2</h3>
<table id="table2" border="1">
 <tr>
         <td>select any option</td>
         <td>
          
   <select>
        <option value="--select--">--select--</option>
  <option value="volvo">Volvo</option>
  <option value="saab">Saab</option>
  <option value="vw">VW</option>
  <option value="audi" >Audi</option>
</select>
         </td>
     </tr>
         <tr>
         <td>select any option</td>
         <td>
          
   <select>
        <option value="--select--">--select--</option>
  <option value="volvo">Volvo</option>
  <option value="saab">Saab</option>
  <option value="vw">VW</option>
  <option value="audi" >Audi</option>
</select>
         </td>
     </tr>
         <tr>
         <td>select any option</td>
         <td>
          
   <select>
        <option value="--select--">--select--</option>
  <option value="volvo">Volvo</option>
  <option value="saab">Saab</option>
  <option value="vw">VW</option>
  <option...

JavaScript

$('#table1 tr').each(function() {										
				   $(this).find('select').change(function(){//alert($(this).val())
					   if($('option[value='+$(this).val()+']:selected').length>1){
						     alert('option is already selected');
						     $(this).val($(this).find("option:first").val());   
						   }
					 });
			});

$('#table2 tr').each(function() {										
				   $(this).find('select').change(function(){//alert($(this).val())
					   if($('option[value='+$(this).val()+']:selected').length>1){
						     alert('option is already selected');
						     $(this).val($(this).find("option:first").val());   
						   }
					 });
			});