Interferons are the protein molecules produced from the

What is introduced into the body during vaccination?

Which of the following organs is a primary lymphoid organ?

$..........$ produces an army of proteins in response to pathogens into our blood to fight with them $:-$

Select the lymphoid organs from the given choices:
$I$. Lymph node $II$. Thymus gland
$III$. Red bone marrow $IV$. Liver
$V$. Spleen $VI$. Osteocytes
$VII$. Peyer's patches
The correct option is:

Passive immunity is obtained through the introduction of which of the following?