What is the primary role of Immunoglobulin A (IgA)?

Show Answers

Serves as a protective barrier on mucosal surfaces against infectionsFunctions mainly as an antibody in the bloodstreamDestroys cells infected by virusesStimulates macrophage activation

Explanation

Option A is correct because IgA primarily protects mucosal surfaces by acting as a barrier against pathogens. Options B, C, and D describe functions associated with other immune components.