Which among the following cell produce the molecule shown in figure?

The correct answer is Option (3) → B-lymphocytes

The figure shows an antibody: four polypeptide chains (two heavy and two light) in a Y shape.

Option (1) Active body cell — Incorrect. Ordinary body cells do not make antibodies; only one kind of lymphocyte does.

Option (2) T-lymphocytes — Incorrect. T-cells do not secrete antibodies; they help B-cells to make them and also carry out cell-mediated immunity.

Option (3) B-lymphocytes — Correct. The figure shows an antibody, with two light and two heavy chains. Antibodies are produced by B-lymphocytes, which release them into the blood in response to pathogens.

Option (4) Both B and T lymphocytes — Incorrect. Only B-lymphocytes produce antibodies.

NCERT Extract:
Acquired Immunity – “… The primary and secondary immune responses are carried out with the help of two special types of lymphocytes present in our blood, i.e., B-lymphocytes and T-lymphocytes. The B-lymphocytes produce an army of proteins in response to pathogens into our blood to fight with them. These proteins are called antibodies. The T-cells themselves do not secrete antibodies but help B cells to produce them.”