Answer :
Final answer:
The complement pathway activated by mannan-binding protein is the option D) lectin pathway, which is part of the body's immune response to pathogens.
Explanation:
The complement pathway that is activated by mannan-binding protein is the lectin pathway. The lectin pathway is triggered by the interaction of certain sugar molecules on the surface of pathogens with mannose-binding lectin (MBL) or ficolins. These carbohydrate-binding proteins, also known as lectins, are found in the plasma and tissue fluids. Once the lectin pathway is activated, it leads to a cascade of immune responses that help to clear infections, similar to the classical and alternative complement pathways.