Question

atopy and anaphylaxis are hypersensitivities in the category
multiple choice
type i only
type iv only
type i and type iv
type i, type ii, and type iii
type i, type ii, type iii, and type iv

Explanation:

Atopy (like allergic rhinitis, asthma) and anaphylaxis are classic examples of Type I hypersensitivity, which is mediated by IgE, mast cells, and rapid immune responses. Type IV is delayed (cell - mediated), Type II is cytotoxic, Type III is immune complex - mediated, so they don't fit. Thus, atopy and anaphylaxis are in Type I only.

Answer:

A. type I only