I have a select box which contains the options and `optgroup` that are generated dynamically using php.Now when I select "ALL" all the other `optgroup`, options should be disabled and when I select any option other than "ALL" the "ALL" option should be disabled

```
<select name="select1" id ="select1" onchange="handleSelect()">
    <option value ="-1">ALL</option>
    <optgroup label="CARS">
        <option value="ford">FORD</option>
        <option value="Nissan">Nissan</option>
    </optgroup>
</select>
<script>
    function handleSelect() {
        var selectVal = $("#select1:selected").text();
        if (selectVal == "ALL") {
            // cannot disable all the options in select box
            $("#select1  option").attr("disabled", "disabled");
        }
        else {
            $("#select1 option[value='-1']").attr('disabled', 'disabled');
            $("#select1 option").attr('disabled', '');
        }
    }
</script>

```

How can I make this working?