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: Histone deacetylases (HDAC) promote: 
 Options:  <0> A less condensed chromatin. <1> A weaker link between histones and DNA in nucleosomes. <2> The acetylation of lysine residues in histones. <3> That the poly (A) tail of the histone messenger RNAs be more extensive. <4> The termination of the transcription and the genetic silencing.

Answer: pharmacology


Question: Question: In general, viruses that have a naked capsid: 
 Options:  <0> They are stable against drying. <1> They are commonly released from the host cell by budding. <2> They are very sensitive to detergents. <3> They are very sensitive to the conditions in the intestinal tract. <4> They can not be neutralized by host antibodies.

Answer: biology


Question: Question: Heparin is: 
 Options:  <0> A plasma protein with no net charge with coagulant function. <1> A glycosaminoglycan with high density of sulphate groups in its structure and anticoagulant function. <2> A protease that facilitates the transformation of prothrombin into thrombin. <3> An extracellular matrix protein with no net charge, which gives rise to highly viscous solutions with a lubricating function. <4> A homopolysaccharide with anticoagulant function thanks to the high density of positive charges in its structure.

Answer:
pharmacology