You will be given a definition of a task first, then some input of the task.
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: When performing the Ames test, what result would reveal that the compound is a mutagen?
Options: <0> Abnormal division in mouse uterus cells. <1> Abnormal growth in mouse. <2> Proliferation of a hamster ovary cell culture. <3> Reversal in the growth characteristics of Salmonella. <4> No option is correct.
Output:
pharmacology