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: Reactions that use copper (I) salts as reagents to replace the nitrogen in the diazonium salts are called reactions of: 
 Options:  <0> Sandmeyer <1> Chichibabin <2> Peterson. <3> Gabriel. <4> Diels-Alder.

Answer: chemistry


Question: Question: How are the proteins involved in the DNA curl and compaction called ?: 
 Options:  <0> Kinases <1> Topoisomerases <2> Histones. <3> Phosphatases <4> DNA nucleases

Answer: chemistry


Question: Question: The reduction of nitriles with diisobutyl aluminum hydride (DIBAL) provides, after the corresponding aqueous acid treatment: 
 Options:  <0> Amines <1> Acids <2> ketones. <3> Aldehydes. <4> None of the above.

Answer:
chemistry