The contribution of b-cells is mainly in Humoral immunity. Thus Option A is correct.
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What is immune system?</h3>
Two types of immunity such as innate immunity is an inbuilt nonspecific immune system protect us from all antigens.
Secondly, we have one more sophisticated adoptive immune system which is up two types humoral immunity and cell mediated immunity.
The adoptive response majorly done by two types of cells such as B and T cells.
This type of immune response use past experience identify a specific foreign threats and counteract them when these threats reappear.
The humoral immune system is activated by external macromolecules antibodies, antimicrobial peptides etc. and protect the extracellular spaces of body.
Hence, Option A is correct.
Learn more about immune system, here:
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