Which actions are involved in the immune response?

The actions involved in immune response are :

Explanation:

The Immune response is defined as the body's response caused by its antigens in the immune system.

In this process the main cells involved are T cells and B cells.

Lymphocytes:

a form of small white blood cell known as a leukocyte with a single round nucleus in the lymphatic system.

Neutrophils:

It is defined as neutrophilic WBC

Monocytes:

It is defined as the phagocytic WBC with a oval nucleus and a grayish cytoplasm.  

not necessarily. higher fitness requires the organism to be reproductive successful. for example, an organism at age 10 with 15 offspring is much more fit than an organism at age 15 with only 5 offspring.