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 chemical reactions of the splicing process of the introns during the maturation of the pre-mRNAs consists of: 
 Options:  <0> An oxidation-reduction reaction. <1> A transesterification reaction. <2> Two sequential transesterification reactions. <3> Three sequential transesterification reactions. <4> A transesterification reaction followed by another oxidation reaction.
[A]: chemistry


[Q]: Question: Iron deficiency anemia is treated with oral or parenteral preparations: 
 Options:  <0> Only ferrous salts should be used orally. <1> Only ferric salts should be used orally. <2> Orally, the most appropriate form is the iron-dextran complex. <3> Orally, the treatment should last a maximum of fifteen days. <4> Only ferrous salts should be used parenterally.
[A]: pharmacology


[Q]: Question: Which of the following administration routes are commonly used for drugs of a peptide and protein nature ?: 
 Options:  <0> Oral. <1> Intravenous, intramuscular and subcutaneous. <2> Oral, intravenous and subcutaneous. <3> Oral, intranasal and inhalation. <4> Oral, intramuscular and intranasal.
[A]:
pharmacology