Amemory b cell can differentiate upon reexposure to a pathogen of which cell type?
ctl
naïve b cell
memory t cell
plasma cell

plasma cell

Explanation:

Memory B cells represent between 5 and 10% of blood lymphocytes and are covered by antigen receptor molecules, when stimulated by some antigen, differentiate into plasma cells. That is, when B cells respond to an infection, they mature and turn into plasma cells. Plasma cells produce antibodies (immunoglobulins) that attack and destroy germs. Memory B cells can be found in many areas of the body. Plasma cells, however, are found mainly in the bone marrow, in the cancellous tissue located on the inner and central bones.

b - the respond is innate and varies over time.

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