Task: Text Categorization
Input (English): Question: In the presence of a patient with Crohn's disease who is going to start treatment with biological anti-TNF therapy (antibodies against tumor necrosis factor alpha), which of the following diagnostic tests is not necessary before initiating such therapy? 
 Options:  <0> Evaluation of the immune stage by lymphocyte count. <1> Serology of hepatitis B virus (HBV). <2> Tuberculin test. <3> Chest x-ray. <4> Serology of the human immunodeficiency virus (HIV).
Output (English): medicine