JSFiddle - React, Tailwind, and code Playground

HTML

<div>
  <form id="ruleListForm" action="/update" method="post">
    <table border="1">
      <thead>
        <tr>
          <th data-field="id"> ID </th>
          <th data-field="ruleName" > RuleName </th>
          <th data-field="fixed" > Fixed </th>
          <th data-field="repeats" > Repeats </th>
          <th data-field="parameter" >Parameter&nbsp;&nbsp; Value &nbsp;&nbsp;&nbsp;&nbsp;overwrite&nbsp;</th>
        </tr>
      </thead>
      <tbody id="ruleListContainer">
        <tr class="rule">
          <td><input type="hidden" name="ruleList[0].id" value="2" /> 2</td>
          <td><input type="hidden" name="ruleList[0].ruleName" value="ABCDEFGH" /> ABCDEFGH</td>
          <td><input type="radio" name="radio_enable_0" value="fixed" /></td>
          <td><input type="radio" name="radio_enable_0" value="true">
            <select name="ruleList[].repeats" disabled style="width: 80px;"> 
              <option value="">--Select--</option>
              <option value="weekly" />
              weekly
              <option value="monthly" />
              monthly
              <option value="quaterly" />
              quaterly
              <option value="half-yearly" />
              half-yearly
              <option value="annually" />
              annually
            </select>
          </td>
          <td>
            <table border="1">
              <tr >
                <td><input type="hidden" name="ruleList[0].ruleAssignmentParameter[0].parameterName" value="Param 9" /> Param 9</td>
                <td><input type="hidden" value="6549" /> 6549</td>
                <td>&nbsp;&nbsp;&nbsp;&nbsp;<input type="text" name="ruleList[0].ruleAssignmentParameter[0].overwriteValue" value=""size="2"height="0.01">&nbsp;or&nbsp; 
                  <select style="width: 80px;">
                    <option value="Minimum Sales"/>Minimum Sales
                    <option value="Service Amount"/>Service Amount
                    <option value="Promotional...

JavaScript

$('input[type="radio"]').on('click', function() {
    var val = $(this).val(),
        selectId = $(this).closest('tr').find('select').first();


    if ($(this).val() === 'true') {
        $(selectId).prop("disabled", false);
    }
    else {
        $(selectId).prop("disabled", true);
    }
});