Which of the following best describes the innate nonspecific immune system?
a targeted and highly specific response to a single pathogen or molecule
a generalized and nonspecific set of defenses against a class or group of pathogens
a set of barrier mechanisms that adapts to specific pathogens after repeated exposure
the production of antibody molecules against pathogens

The correct answer is second statement.

Explanation:

The innate immune system is always nonspecific or generalized, this signifies that anything, which is determined as non-self or foreign is a target for the innate immune reaction. The system gets instigated by the existence of antigens and their chemical characteristics. Thus, a generalized and nonspecific set of defenses against a group or category of pathogens illustrates the innate nonspecific immune system.