Which antibody is known as the secretory antibody?

Identify the statement that is $\text{NOT}$ correct.

Interferons protect non-infected cells from further viral infection. These are included in which of the following barriers of innate immunity?

Match List-$I$ with List-$II$ :

List-$I$	List-$II$
$a$. Cellular barrier	$i$. Interferons
$b$. Cytokine barrier	$ii$. Mucus
$c$. Physical barrier	$iii$. Neutrophils
$d$. Physiological barrier	$iv$. $HCl$ in gastric juice

Choose the correct answer from the options given below:

In higher vertebrates, the immune system can distinguish between self and non-self cells. Due to genetic or other unknown reasons, the immune system sometimes loses this property and starts attacking self-cells, resulting in:

Which of the following is an autoimmune disease?