<?php

    $sql = "SELECT Q_body, Q_ID FROM s_evaluation_questions WHERE Ev_ID='1'";
    $result = $conn->query($sql);

    ?>

    <?php

    if ($result->num_rows > 0)
    {

    ?>
    <form action="AnswerS.php" method="POST">
    <table align="right"  id="keywords" cellspacing="0" cellpadding="0">
        <thead>
                <tr>
                    <th colspan="4">  </th>
                    <th>Question</th>
                </tr>
        </thead>

     <tbody>
    <?php
        while($row = $result->fetch_assoc())
        {   $answer="s".$row["Q_ID"];
             ?>
                    <tr>
                    <td>
                 <input type="hidden" name="Q_ID" value="<?php echo $row["Q_ID"]; ?>" >
                    <input type="radio" name=<?php echo $answer?> value="Bad" >Bad
                    <input type="radio" name=<?php echo $answer?> value="Good"> Good
                    <input type="radio" name=<?php echo $answer?> value="VeryGood"> Very Good
                    <input type="radio" name=<?php echo $answer?> value="Excellent"> Excellent</td>
                    <td align="right"> <?php echo $row["Q_body"]?></td>
                    </tr>

                    <?php   } ?>

    </tbody>

        </table></br></br></br></br></br></br></br>
        <input type="submit" value="Send" />
                </form>
        <?php

        ?></div>
    <?php
    } else
    {echo "not allowed";}


and on the AnswerS.php page I suppose to store the answers on db as the following:
$UID='1';
$answer=$_POST['answer'];
$Q_ID= $_POST['Q_ID'];


    $sql = "INSERT INTO s_evaluation_answers(Q_ID, A_body, UID) VALUES($Q_ID, $answer, $UID) ";
$result = $conn->query($sql);

if ($result === TRUE) {
    echo "done" ;
    }
    else {
        echo "Error: " . $sql . "<br>" . $conn->error;
    }