Which of the following correctly describes the physical interaction between an antigen-presenting cell and a naive helper T-lymphocyte during activation?

a) The antigen-presenting cell directly engulfs the helper T-lymphocyte.
b) The helper T-lymphocyte releases cytokines that activate the antigen-presenting cell.
c) The antigen-presenting cell secretes antibodies that neutralize the helper T-lymphocyte.
d) The helper T-lymphocyte undergoes apoptosis upon contact with the antigen-presenting cell.