Final answer:
The correct answer is Active Immunity. Vaccines stimulate the immune system to produce its own immune response against a specific pathogen.
Step-by-step explanation:
The correct answer is A) Active Immunity.
Vaccines bring about active immunity, which is when the immune system is stimulated to produce its own immune response against a specific pathogen. This is achieved by introducing a weakened or inactivated form of the pathogen or its components into the body through vaccination.
For example, when a person receives a flu vaccine, it contains weakened or inactivated flu viruses.
This stimulates the person's immune system to produce antibodies that can recognize and attack the flu viruses if they are encountered in the future, providing protection against the flu.