Additional choices based on multiple select values

HTML

<label for="firstChoice">First Choice</label>
<select id="firstChoice" name="firstChoice">
    <option value="">Select</option>
    <option value="Option 1">Option 1</option>
    <option value="Option 2">Option 2</option>
    <option value="Option 3">Option 3</option>
    <option value="Option 4">Option 4</option>
</select>
<label for="secondChoice">Second Choice</label>
<select id="secondChoice" name="secondChoice">
    <option value="">Select</option>
    <option value="Option 1">Option 1</option>
    <option value="Option 2">Option 2</option>
    <option value="Option 3">Option 3</option>
    <option value="Option 4">Option 4</option>
</select>
<div class="additional">
    Stuff goes here
</div>

CSS

body {
    font-family:sans-serif;
    font-size:0.8em;
}
label, select {
    display:block;
    padding:0.3em;
}
select {
    margin-bottom:1em;
}
.additional {
    border-bottom:1px solid #DDD;
    border-top:1px solid #DDD;
    margin:1em 0;
    padding:0.8em 0;
    display:none;
}

JavaScript

var arr;
var $select = $('#firstChoice,#secondChoice');
$select.on('change', function () {
    var str = "Option 1";
    if ($('#firstChoice').val() === str || $('#secondChoice').val() === str) {
        $('.additional').show();
    } else {
        $('.additional').hide();
    }
});