Remove action plugin

Thank you kaiser,
your comment is helpful but insufficient, so the solution is :

to remove function in other class in wordpress :

    remove_action('register_form', array(Theme_My_Login_Custom_Passwords::get_object(),'password_fields' ) );

Thank you

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)