JSFiddle - React, Tailwind, and code Playground

HTML

<div class="carr">carrière 1</div>
<div class="carr">carrière 2</div>
<div class="carr">carrière 3</div>
<div class="carr">carrière 4</div>
<div class="carr">carrière 5</div>
<div class="carr">carrière 6</div>
<div class="carr">carrière 7</div>
<div class="carr">carrière 8</div>
<select id="foo">
    <option value="-1">choissiez une carrière</option>
    <option value="1">1</option>
    <option value="2">2</option>
    <option value="3">3</option>
    <option value="4">4</option>
    <option value="5">5</option>
    <option value="6">6</option>
    <option value="7">7</option>
    <option value="8">8</option>
</select>

CSS

.carr {
    display:none;
}

JavaScript

$('#foo').change(function () {
    n = this.value-1;
    $('.carr').each(function () {
       $(this).css({
            "display": ($(this).index('.carr') == n) ? 'block' : 'none'
        })
    })
})