Answer:
None of the above
acquired immunity or adaptive immunity
Option A, immunotherapy is closest
Explanation:
The correct answer does not seem to be a part of the option set available to fill in the blank.
Passive immunity in which a mother passes down cell receptors known as antibodies from their own immune system to their off-spring is a unique subsect of the acquired immunity (or adaptive immunity) system. It can also be called the antibody-mediated immunity. Without having ever been exposed to the pathogen themselves, the offspring will still have acquired the antibodies to recognize, bind, and neutralize antigens (marker molecules associated with specific pathogens). This occurs because the mother was likely previously exposed and developed those antibodies.
This type of immunity is a direct opposite of cell-mediated immunity, which does not involve the use of antibodies, only cells combating a pathogen, which then stimulates the production of antibodies. Thus, option C is out.
It is also a direct opposite of innate immunity because the offspring's immune system did not produce these antibodies on its own; rather, the mother passed them down, hence why it is called passive immunity. This eliminated option D.
Autoimmunity is an occurrence in which a person's immune system attacks their own cells and tissues as if they are foreign invading pathogens. These conditions can cause harm to the person. This is not what occurs with passive immunity. Option B is eliminated.
Lastly, immunotherapy is the exogenous or activation suppression of the immune system by chemical and or pharmacological means for the purpose of treating a condition, like cancer or allergies. Passive immunity does not use these agents to produce immunologic effects, though a form of antibodies are given to patients. Option A is out.
Therefore, none of these answers accurately fill in the blank. Passive immunization is a type of acquired immunity or adaptive immunity. If one must choose from the answer set, option A, immunotherapy is the closest.