Within the creditcard field set, create a field set belonging to the class optionGroup. Within this field set, create four label elements. Within each label, create an option button belonging to the card field followed by an inline image belonging to one of four credit card companies. The field values associated with the four option buttons are diners, discover, master, and visa, and the inline images are diners.png, discover.png, master.png, and visa.png, respectively.