You Are Very Allergic to Ragweed Pollen, Which Gives You

You are very allergic to ragweed pollen, which gives you terrible hay fever. You remember from your own microbiology class that for you to have a reaction to this allergen every year, you must have become sensitized to it. Which step is not involved in or does not lead to sensitization?

A) On first contact with the allergen, an antibody response is induced in the person.
B) Helper T cells activate naive B cells, which proliferate and differentiate.
C) Plasma cells produce IgE specific for the antigen that initiated the response. 
D) The Fc portion of the IgE binds to receptors on mast cells or basophils, positioned so that their Fab sites are free.
E) These are all steps involved in sensitization.