Answer the following question given this paragraph: 

Plasma cells are activated B cells that secrete antibodies. Antibodies are large, Y-shaped proteins that recognize and bind to antigens. Plasma cells are like antibody factories, producing many copies of a single type of antibody. The antibodies travel throughout the body in blood and lymph. Each antibody binds to just one kind of antigen. When it does, it forms an antigen-antibody complex (see Figure below ). The complex flags the antigen-bearing cell for destruction by phagocytosis .


Q: What do you call large, y-shaped proteins that recognize and bind to antigens?

 Choices:

- proteins

- membranes

- parasites

- antibodies

A:
antibodies
