JSFiddle - React, Tailwind, and code Playground

HTML

<select onchange='symbolChange(this);'>
                 <option name='USD'>USD</option>
                 <option name='EUR'>EUR</option>
        </select>
<div id='currencySymbol'>
        $
    </div>

JavaScript

function symbolChange(obj) {
    var val = obj.value;
    switch (val) {
        case 'USD':
            document.getElementById("currencySymbol").innerHTML= "$";
            break;
        case 'EUR':
            document.getElementById("currencySymbol").innerHTML= "€";
            break;
        default :
            document.getElementById("currencySymbol").innerHTML= "$";
            break;
    }
}