Task: Text Categorization
Input (English): Question: In IgE-mediated hypersensitivity reactions: 
 Options:  <0> Eosinophils and mast cells play an important role. <1> There are no cellular elements involved. <2> Antibody-mediated cytotoxicity reactions play a key role. <3> There are no elements of the immune system involved in atopy. <4> The IgE immunoglobulin receptor does not intervene.
Output (English): medicine