What is the main lymphoid organ in the human body?

Step-by-step solution

The primary lymphoid organs in the human body are the bone marrow and thymus, where immature lymphocytes differentiate into antigen-sensitive lymphocytes.The thymus is quite large at the time of birth but keeps reducing in size with age. By the time puberty is attained, it reduces to a very small size. The spleen mainly contains lymphocytes and phagocytes. It acts as a filter of the blood by trapping blood-borne microorganisms. It also has a large reservoir of erythrocytes. The bone marrow is the main lymphoid orga