Answer :
Statement (a) and (d) describe active immunity, involving the body's response to pathogens or vaccines. Statement (b) and (c) describe passive immunity, which involves the direct provision or transfer of antibodies. Both active and passive immunity are essential for disease prevention and treatment.
To group the provided statements into active or passive immunity, let's review each one:
- a. Results when a person has had previous exposure to a disease or pathogen - This describes active immunity because it involves the body's immune response to previous exposure to a pathogen and the formation of immunological memory.
- b. Bypasses the body's immune response to afford the benefit of immediate antibody availability - This is passive immunity because it involves the direct provision of antibodies without the body's immune system responding to the pathogen.
- c. Occurs when antibodies are transferred from one person to another - This refers to passive immunity as it involves the transfer of antibodies between individuals.
- d. Results when a person receives immunizations against a disease to stimulate the production of a specific antibody - This describes active immunity because vaccines stimulate the body's own immune system to produce antibodies.