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.

[EX Q]: Question: Liquid chromatography using linked stationary phases can be divided into normal phase and reverse phase phases. In this context it can be said that: 
 Options:  <0> The main separation mechanism in reverse phase is the distribution, while adsorption also plays a very important role in the normal phase. <1> In normal phase chromatography, a large number of non-polar stationary phases can be used. <2> The main separation mechanism in normal phase is the distribution, while the adsorption plays a very important role in the reverse phase. <3> In reverse phase chromatography, the stationary phase is polar and the non-polar eluents. <4> In reverse phase chromatography, a large number of polar stationary phases can be used.
[EX A]: chemistry

[EX Q]: Question: They are involved in the lytic action of cytotoxic T lymphocytes: 
 Options:  <0> Granzimas <1> Opsonins. <2> Histamines <3> Integrins <4> Cathepsins.
[EX A]: biology

[EX Q]: Question: The reaction of an alkene with metachloroperbenzoic acid causes a cyclic ether which is called: 
 Options:  <0> Furano <1> Dioxane <2> Epoxide <3> Azirano <4> Lactone
[EX A]:
chemistry