JSFiddle - React, Tailwind, and code Playground

HTML

<form>
<fieldset class="select">
    <select id="options">
        <option>Choose One...</option>
        <option>first</option>
        <option>second</option>
        <option>third</option>
    </select>
</fieldset>
<fieldset class='optional' id="first">
    <legend>First</legend>
    <input type="text" />
</fieldset>
<fieldset class='optional' id="second">
    <legend>Second</legend>
    <input type="text" />
</fieldset>
<fieldset class='optional' id="third">
    <legend>Third</legend>
    <input type="text" />
</fieldset>
</form>

CSS

.optional{
display:none;
}

JavaScript

$('#options').change(function(){
    selection = $(this).val();
    $('.optional').hide();
    $("#" + selection).show();
})