What do plasma cells produce?

Plasma cells are a key component of the immune system, specifically derived from B lymphocytes (B cells). Their primary function is to produce antibodies, also known as immunoglobulins. These antibodies are essential for identifying and neutralizing foreign objects like bacteria and viruses, playing a critical role in the adaptive immune response.

When B cells recognize an antigen, they become activated and differentiate into plasma cells, which are capable of synthesizing large quantities of a specific antibody. These antibodies have the ability to bind to antigens, marking them for destruction by other immune cells or neutralizing their harmful effects directly.

Hormones, red blood cells, and platelets serve different functions and are produced in various parts of the body, such as glands or the bone marrow. Hormones are signaling molecules secreted by endocrine glands, red blood cells transport oxygen throughout the body, and platelets are involved in blood clotting. Thus, the unique ability of plasma cells to specifically produce antibodies makes this choice the correct answer.