<select name="test">
<option value="Sony" name="do_signup">Sony</option>
<option value="Toshiba">Toshiba</option>
<option value="Acer">Acer</option>
<option value="Asus">Asus</option>
</select>
$data = $_POST;
if( isset($data['test']) ){
$all_anime_msql = mysqli_query($connection, "SELECT * FROM `all_anime` WHERE `rating` != 0 ORDER BY `rating` DESC");
}