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: In which of the drugs with antiviral activity does the purine base called guanine appear?
Options: <0> Lamivudine <1> Zidovudine <2> Ribavirin <3> Acyclovir <4> Didanosine
A:
pharmacology