tjekke om radio button er checked hvordan?

hvordan tjekker jeg om alle felter er checked?

Her er min form:

<form action="formhandler.php?step=<?php echo $_GET['step'] ?>" method="post">

<tr>
<td width="200">Spørgsmål</td><td width="100" align="center">Super godt</td><td width="100" align="center">Godt</td><td width="100" align="center">Mindre godt</td><td width="100" align="center"    >Latterligt</td>
</tr>
<?php
$step = $_GET['step'];

$query = mysqli_query($GLOBALS['db'], "SELECT * FROM tblquestion WHERE category = '".$_GET['step']."'");
    while($result = mysqli_fetch_array($query)){

        echo "<tr>";
        echo     "<td>".$result['question']."</td>
               
                <td align=\"center\"><input type=\"radio\" name=\"".$result['id']."\" value=\"1\" /></td>
                <td align=\"center\"><input type=\"radio\" name=\"".$result['id']."\" value=\"2\" /></td>
                <td align=\"center\"><input type=\"radio\" name=\"".$result['id']."\" value=\"3\" /></td>
                <td align=\"center\"><input type=\"radio\" name=\"".$result['id']."\" value=\"4\" /></td>";
   
        echo "</tr>";
    };
?>
<tr height="50">
<td colspan="5" align="right"><input type="submit" name="submit" value="næste" /></td>
</tr>
</form>

og min action:

if(!isset($_SESSION['question']) && !is_array($_SESSION['question'])){
$_SESSION['question'] = array();
};

if(isset($_POST['submit'])){
    foreach($_POST as $id => $answer){

            $_SESSION['question'][$id] = $answer;
    };
};