Which of the following is an autoimmune disease?

After maturation,in primary lymphoid organs,the lymphocytes migrate for interaction with antigens to secondary lymphoid organs like:
$A.$ thymus $B.$ bone marrow $C.$ spleen $D.$ lymph nodes $E.$ Peyer's patches
Choose the correct answer from the options given below:

After birth,an infant receives antibodies $IgA$ through colostrum from the mother. This is an example of . . . . . . immunity.

The principle of vaccination is based on which property of the immune system?

Plasma cells are .....

Identify the correct group of primary lymphoid organs.