The secretion of interferon is inhibited by . . . . . . .

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.

Match the following columns:

Column-$I$	Column-$II$
$P$. Physical barriers	$I$. Acid in stomach,saliva in mouth,tears from eyes
$Q$. Physiological barriers	$II$. Skin,mucus coating of epithelium lining the respiratory,gastrointestinal and urogenital tracts
$R$. Cellular barriers	$III$. Interferons
$S$. Cytokine barriers	$IV$. Polymorphonuclear leukocytes ($PMNL$-neutrophils),monocytes,$NK$ cells,macrophages

Primary lymphoid organs $- P$
Secondary lymphoid organs $- Q$
$I -$ Appendix, $II -$ Peyer's patches of small intestine,
$III -$ Thymus, $IV -$ Spleen, $V -$ Lymph node, $VI -$ Bone marrow, $VII -$ Tonsils
Select the correct option for $P$ and $Q$.
$\quad P \quad \quad Q$

Antibodies produced by $B$-lymphocytes are responsible for:

What is an antigen?