Final answer:
True. Antigen-antibody binding can block adhesion of bacteria and viruses to mucosa.
Step-by-step explanation:
True. Antigen-antibody binding can block adhesion of bacteria and viruses to mucosa. When an antigen, such as a pathogen or toxin, enters the body and binds to receptors on the mucosal surface, antibodies can recognize and bind to the antigen. This binding can prevent the pathogen or toxin from attaching to the mucosal cells, effectively blocking their adhesion.