Instructions: 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.
Input: Question: The prozone effect of a turbidimetric analysis can be detected by measuring the absorbance:
Options: <0> After an ultracentrifugation. <1> Previous concentration of the sample. <2> After dilution of the sample. <3> Once the sample was treated with SDS. <4> Two consecutive times.
Output:
chemistry