JSFiddle - React, Tailwind, and code Playground

HTML

<select>
    <option value="-1">---</option>
    <option value="alimentation">Choix 1</option>
    <option value="2">Choix 2</option>
    <option value="3">Choix 3</option>
    <option value="4">Choix 4</option>
    <option value="5">Choix 5</option>
    <option value="6">Choix 6</option>
    <option value="7">Choix 7</option>
    <option value="8">Choix 8</option>
</select>

<div id="choix">
	<div class="alimentation">Alimentation</div>
	<div class="alimentation">Alimentation bis</div>
	<div class="2">2</div>
	<div class="3">3</div>
	<div class="4">4</div>
	<div class="5">5</div>
	<div class="6">6</div>
	<div class="7">7</div>
	<div class="8">8</div>
</div>

JavaScript

function selectionDone(e){
	
	var showAll = (e.target.value == "-1") ? 1 : 0,
		divs = document.getElementById("choix").children,
		i = 0,
		l = divs.length;

	for (; i<l; i++) {

		divs[i].style.display = (showAll) ? "block" : "none";

	}
	
	var toShow = document.getElementsByClassName(e.target.value);

	i = 0;
	l = toShow.length;

	if (!showAll) for(; i<l; i++) toShow[i].style.display = "block";

}

var select = document.querySelector("select");

select.children[0].setAttribute("selected", "");

select.addEventListener("change", selectionDone, false);