In which of the following organs do immature lymphocytes differentiate into antigen-sensitive lymphocytes?

The antibodies are produced by the

Read the given statements carefully and identify the incorrect statements.
$(1)$ In active acquired immunity,antibodies are directly injected into the body.
$(2)$ Vaccination is considered under passive acquired immunity.
$(3)$ The human body distinguishes between self and non-self with the help of $Tc$ cells.
$(4)$ Innate immunity consists of four types of barriers.

$.........$ is responsible for graft rejection.

Which cells are involved in the immune response?

Match the columns:

Column-$I$	Column-$II$
$(a)$ Main lymphoid organ	$(1)$ Thymus
$(b)$ $MALT$	$(2)$ Spleen
$(c)$ Lobe-like organ arranged near heart	$(3)$ Bone marrow
$(d)$ Large bean-shaped organ	$(4)$ It constitutes $50\%$ of lymphoid tissue