<?php
 
$responses = array('A=1', 'B=2', 'C=3');
 
foreach ($responses as $response) {
    $key = explode("=", $response)[0];
    $value= explode("=", $response)[1];
 
        if($key != "" && $value != "") {
        $data[$key] = $value;    // <<<<< "Illegal offset type" error on this line
    }
}
?>
<!-- displaying the results of the query -->
<table>
    <?php foreach ($data as $key => $value): ?>
    <tr><td><?php echo $key; ?></td><td><?php echo $value; ?></td></tr>
    <?php endforeach; ?>
</table>

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