Final answer:
IgA is the antibody isotype associated with mucosal immunity. It is abundantly found in various bodily secretions and plays a critical role in neutralizing pathogens and protecting the mucosa.
Step-by-step explanation:
The antibody isotype associated with mucosal immunity is IgA.
IgA is abundantly found in tears, saliva, breast milk, and secretions of the gastrointestinal and respiratory tracts. It plays a crucial role in preventing infection of the mucosa by binding and neutralizing pathogens. Secretory IgA, which is assembled in a dimeric form, traps pathogens in mucus for later elimination from the body.