Task: Text Categorization
Input (English): Question: Azidothymidine (AZT) used against the human immunodeficiency virus: 
 Options:  <0> It binds to the cellular RNA polymerase and blocks transcription. <1> It binds to the early promoter of the virus and prevents its recognition by RNA polymerase. <2> Antagonizes the phosphorylation of nucleosides, thus inhibiting the synthesis of viral DNA. <3> Blocks the transport of thymidine to the cellular interior. <4> Inhibits transcriptase
Output (English): biology