A protease cleaves an antibody into three fragments. Two of these fragments are identical and are composed of a light polypeptide chain and a heavy polypeptide chain. The third fragment is composed solely of heavy chains. Which of the following statements regarding the identical fragments is true?

MCQs on the immune system, including innate and adaptive immunity, the cells involved in each of process of the immune system and their role in the immune response, and how antibodies are used to confer immunity for future potential exposures.