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: Question: A parameter of great importance in chromatography is the equivalent height of theoretical plate (H). The van Deemter equation describes the behavior of a filler column for gas-liquid chromatography, where H = A + (B / u) + Cu, so that: 
 Options:  <0> C is the parameter that is taken as a measure of the quality of the filling of the column. <1> A is the coefficient that collects the contribution of longitudinal diffusion. <2> B is the parameter that is related to the resistance to the transfer of matter that opposes the stationary phase. <3> u is the linear velocity of the mobile phase. <4> B is canceled in columns without filling.

Answer: chemistry


Question: Question: The lithium dialkyl-heptarate reacts with alkyl halides to produce, by formation of carbon-carbon bonds between the alkyl group of the halide and the alkyl group of the dialkyl acetate: 
 Options:  <0> Alcanes. <1> Alquenos <2> Alquinos. <3> Aromatics <4> Piranos.

Answer: chemistry


Question: Question: In order to check the efficacy of a treatment to stop smoking, a control group (placebo) is compared with a treated group. For groups to be comparable it is important that they do not differ much in the age of the participants. We are informed that the average age in the control group is 52 years and that in the treated group it is also 52 years. From this information we can say that: 
 Options:  <0> The groups do not differ with respect to the distribution of the age variable. <1> If the study is well designed, it can not give us the same average age in both groups. <2> To compare the distribution of the age variable in both groups, it would be convenient to know a measure of dispersion as the standard deviation in addition to the mean. <3> For the final conclusion it does not matter the distribution of age in both groups, only if the treatment is effective or not. <4> If, in addition to the mean, the median and the fashion agree, we can affirm that the groups do not differ with respect to the distribution of the age variable.

Answer:
medicine