/**
  * Method to get a list of options for a list input.
  *
  * @return	array		An array of JHtml options.
  */
 protected function getOptions()
 {
     $document = JFactory::getDocument();
     $language = $document->getLanguage();
     $merchantCategories = BFCHelper::getMerchantCategories();
     $options = array();
     if ($merchantCategories) {
         foreach ($merchantCategories as $merchantCategory) {
             $currOpt = JHtml::_('select.option', $merchantCategory->MerchantCategoryId, BFCHelper::getLanguage($merchantCategory->Name, $language));
             $currOpt->checked = null;
             $options[] = $currOpt;
         }
     }
     $options = array_merge(parent::getOptions(), $options);
     return $options;
 }
<?php

$base_url = get_site_url();
$language = $GLOBALS['bfi_lang'];
$categoriesoptions = array();
$merchantCategories = BFCHelper::getMerchantCategories();
foreach ($merchantCategories as $category) {
    $categoriesoptions[$category->MerchantCategoryId] = $category->Name;
}
?>
<form method="POST" action="<?php 
echo $base_url;
?>
/bfi/settings/list-merchants-form-process">
  Title:<br>
  <input type="text" name="title" value=""><br>
  Route:<br>
  <input type="text" name="route" value=""><br>
  Merchant Categories:<br>
  <?php 
foreach ($categoriesoptions as $key => $val) {
    ?>
  <input type="checkbox" name="categories[<?php 
    echo $key;
    ?>
]" value="<?php 
    echo $val;
    ?>
"> <?php 
    echo $val;
    ?>