You are exposed to the same pathogen twice in your lifetime. Which of the following is true?

A.) Your body will fight the second exposure much slower because it has already
used up all its antibodies against that antigen.

B.) The reaction times will be almost equal.

C.) You cannot be exposed to the same pathogen twice in your life because you
already destroyed those pathogens with your Killer T cells.

D.) Your body will fight the second exposure much quicker because it has stored
memory cells against that specific antigen.