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.
Q: Question: Among the equipment used for the mixing of powders are the rotary mixers, which are usually used when the powder:
Options: <0> It has poor flow. <1> It flows freely. <2> It has an angle of repose> 90. <3> It is high intensity. <4> It contains moisture.
A:
pharmacology