how to show element as respond to user dropdown selection

[J.D]

Make the elements hidden on load and do something like:

$w.onReady(() => {
    $w('#dropdown1').onChange(event => {
    switch (event.target.value){ 
        case '1':
            $w('#elementX').show();
            break;
        case '2':
            $w('#elementY').show();
            break;
        case '3':
            $w('#elementZ').show();
            break;
        //etc...
       }
    })
})