Using wp_dropdown_categories change select and option values

Hi, I am in need of some help with a wordpress function. I've been looking for a solution for a while now and have not been able to figure it out. The code I am using and referring to is -

<?php

//first get the current term
$current_term = get_term_by( 'slug', get_query_var( 'term' ), get_query_var( 'taxonomy' ) );

//then set the args for wp_dropdown_categories
 $args = array(
    'child_of' => $current_term->term_id,
    'taxonomy' => $current_term->taxonomy,
    'hide_empty' => 0,
    'hierarchical' => true,
    'depth'  => 2,
    'title_li' => '',
        'show_option_all' => All,
        'hide_if_empty' => true
    );
 wp_dropdown_categories( $args );
?>

I want to know how can I modify the select dropdown so that I can add values and classes to <select> and <option>'s ? Any help would be greatly appreciate it. Thanks.