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: The reaction of 1H-indole with electrophiles takes place selectively on the atom in position: 
 Options:  <0> one. <1> two. <2> 3. <3> Four. <4> 5.

A: chemistry
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Q: Question: In the translation of prokaryotes, the first tRNA: 
 Options:  <0> It is introduced in site A. <1> Join a methylated amino acid. <2> It is accompanied by the IF2 factor. <3> It is paired with a UGA start codon. <4> Always join serina.

A: biology
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Q: Question: With respect to the distribution coefficient of a solute between two partially miscible liquids: 
 Options:  <0> Because it is a quotient between solute concentrations in the two phases, it is independent of temperature. <1> It does not depend on the total amount of solute in both parts. <2> It is useful to determine the molar mass of the solute. <3> If one phase is water and the other an organic solvent, it is usually used in medical and environmental chemistry to know the distribution of drugs and contaminants between these two types of media. <4> It only has physical significance when the liquid phases are in contact through a semipermeable membrane.

A:
chemistry
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