What type of immunity results from the production of antibodies by the immune system?

The correct answer is active immunity because it directly involves the immune system's own response to pathogens. When an individual is exposed to a pathogen, their immune system responds by producing specific antibodies designed to target that pathogen. This process can happen naturally, such as through infection, or can be induced artificially, for instance, through vaccination. In both scenarios, the result is the immune system generating its own antibodies, leading to long-lasting immunity against future infections by that pathogen.

The term active immunity encompasses both natural and acquired mechanisms, emphasizing that the individual’s immune system is actively engaged in producing the necessary antibodies. This is in contrast to passive immunity, where antibodies are received from another source, such as mother to child during breastfeeding, without the child's immune system actively producing them. Natural immunity refers specifically to immunity resulting from infections, while acquired immunity usually suggests that it is gained from external sources, like vaccines, but still refers to the active production of antibodies by the immune system. Thus, the defining characteristic of active immunity is that it is the body's own immune response leading to the production of antibodies.