Q: In this task, you are given a question and answer options for that question. Using this information, you have to classify each text into different topics: medicine, nursery, psychology, chemistry, pharmacology, biology.
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
A:
biology