Which of the following best describes the purpose of injecting live, weakened microbes into the human body?

a
to stimulate the replication of genes that direct the synthesis of hormones
b
to stimulate the immune system to fight future invasions by these microbes
c
to stimulate the production of microbes to protect the organism from future attacks
d
to stimulate the production of antigens to prevent infections from occurring

b

to stimulate the immune system to fight future invasions by these microbes