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...

JavaScript

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