storing value from radio button to database with looping

I am trying now to get the value of every radio button to store in a database. The trick is I'm using while loop to display the question and the choices.

Here is my code in displaying the questions and choices.

class questions{
        function __construct(){
            $db= new dbConnect();       
        }
        public function fetchRandom()
        {
            $qr=mysql_query("SELECT * FROM questionaires INNER JOIN choices ON questionaires.q_id=choices.q_id WHERE RAND()<(SELECT ((10/COUNT(*))*10) FROM questionaires) ORDER BY RAND() LIMIT 10");
            $c=0;
            echo "<table border='3' align='center' bordercolor='#CCCCCC'>
            <tr> 
            <th>Number:</th>
            <th>Question</th>
            </tr>";
            while($row=mysql_fetch_array($qr))
            {   
                $c++;
                echo "<tr>";
                echo "<td>" . $c . "</td>";
                echo "<td>";
                echo $row['question'] . "<br>";
                $ans_arr=array($row['choice_a'],$row['choice_b'],$row['choice_c'],$row['choice_d']);
                shuffle($ans_arr);
                echo "<input type='radio' name='ans".$c."' value='".$ans_arr[0]."'>".$ans_arr[0]."</input><br>";
                echo "<input type='radio' name='ans".$c."' value='".$ans_arr[1]."'>".$ans_arr[1]."</input><br>";
                echo "<input type='radio' name='ans".$c."' value='".$ans_arr[2]."'>".$ans_arr[2]."</input><br>";
                echo "<input type='radio' name='ans".$c."' value='".$ans_arr[3]."'>".$ans_arr[3]."</input><br>";
                echo "</td>";
                echo "</tr>";
            }
            echo "</table>";
        }
    }

How can I store the answer of the user to database. Little help will be appreciated. Because I don't know how to code it from scratch. Thank you.