<select class="form-control" name="parent_cat" id="parent_cat">
<option selected="selected"><?php echo $array[3]; ?></option>
<?php
while ($array2 = mysqli_fetch_all($par_cat, MYSQL_NUM)){
echo '<option value="'.$array2['0'].','.$array2['1'].'"> '.$array2['0'].' - '.$array2['1'].'</option>';
}?>
</select>