file.php

<?php

add_action('add_meta_boxes', 'maximize_lead_mb_add');

function maximize_lead_mb_add() {
    add_meta_box(
        'maximize_lead-id',
        'Maximize Lead Page',
        'maximize_lead_cb',
        'page',
        'side'
    );
}

function maximize_lead_cb() {
    global $post;
    global $wpdb;
    $table = $wpdb->prefix . "maximize_lead";
    $pages = $wpdb->get_results("SELECT id, title FROM $table");
    $values = get_post_custom($post->ID);
    $mlSelected = $values['maximize_lead_page'];
    wp_nonce_field('maximize_lead_mb_nonce', 'maximize_lead_nonce');
    $mlCurrentSelected = $mlSelected[0];
?>

<h4>Select a Maximize Lead Page</h4>
<select name="maximize_lead_page"
        id="maximize_lead_page">
  <option <?php if($ezleadproCurrentSelected == "0"){ echo "selected='selected'"; } ?>>None</option>
  <?php
    foreach($p as $pages) {
        $id = stripslashes($p->id);
        $title = stripslashes($p->title);
        $sel = $mlCurrentSelected == $id ? "selected='selected'" : "";
        echo "<option $sel value='$id'>$title</option>";
    }
  ?>
</select>

<?php 
}