The correct option is A B lymphocytes
Antibodies are proteins which can bind and destroy pathogens and their toxins. Thus, release of antibodies is part of the defense mechanism against these pathogens. Lymphocytes or WBCs are responsible for the immunity of the body. Based on the site of maturation the lymphocytes are classified into B lymphocytes and T-lymphocytes. The B-lymphocytes release antibodies and are matured in the bone marrow. Whereas the T-lymphocytes are matured in thymus and they stimulate B-lymphocytes to make antibodies.