Given the task definition and input, reply with output. 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: The use of monolithic columns and continuous beds in liquid chromatography is already very common. To this end:
Options: <0> Microporous membranes are used so that the interaction between a solute and the matrix takes place in the final part of the pore. <1> A separation medium is introduced with a greater degree of continuity than the stationary particle phase so that the mobile phase is forced to traverse the large pores of the medium, improving mass transport. <2> Monodisperse particles are used as a stationary phase in order to improve mass transfer. <3> Flexible organic gels are used from microporous polymers in order to decrease the flow rates. <4> Columns filled with small particles of polymerized silica are used.
chemistry