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: What simple reinforcement programs produce a more stable response pattern ?: 
 Options:  <0> Those of fixed ratio. <1> Those of variable reason. <2> Those of fixed interval. <3> Those of variable interval. <4> All reinforcement programs produce similar response rates.
[A]: psychology


[Q]: Question: Relating to topoisomerases: 
 Options:  <0> They are enzymes that convert the D-amino acids into L-amino acids. <1> They are enzymes that synthesize DNA. <2> They are enzymes that participate in the union of the subunits of the ribosome. <3> They are enzymes that denature DNA. <4> DNA gyrase is a special toposiomerase.
[A]: chemistry


[Q]: Question: When the electromagnetic radiation passes from the air to a medium like glass its wavelength: 
 Options:  <0> It remains unchanged. <1> Increase approximately 10 nm. <2> Increase approximately 100 nm. <3> It decreases approximately 1 nm. <4> It decreases approximately 200 nm.
[A]:
chemistry