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.
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Question: 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.

Answer: chemistry


Question: Question: The papillary muscles: 
 Options:  <0> They contract atrio-ventricular valves. <1> They prevent the reflux of blood to the atria. <2> They avoid the eversion of the semilunar valves. <3> They form the interventricular septum. <4> They are formed by visceral smooth muscle.

Answer: biology


Question: Question: Which of the following enzymes catalyzes a hydrolytic reaction ?: 
 Options:  <0> Lactate dehydrogenase. <1> Chymotrypsin <2> Fumarasa <3> Triose phosphate isomerase. <4> RNA polymerase

Answer:
chemistry