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.

Question: The valvulopathy that triggers an overload of volume in both the left atrium and ventricle is: 
 Options:  <0> Mitral stenosis. <1> Mitral insufficiency <2> Aortic stenosis. <3> Aortic insufficiency <4> Tricuspid insufficiency.
pharmacology

Question: In strict vegetarians, a lack of one of the following vitamins may appear: 
 Options:  <0> B12 vitamin. <1> Vitamin C. <2> Retinol <3> Folate <4> Niacin
nursery

Question: The most commonly used data to study the phylogenetic relationship between bacteria is: 
 Options:  <0> The cytosine-guanine composition of their DNA. <1> The degree of DNA-DNA hybridization. <2> The amino acid sequence of ribosomal proteins. <3> The nucleotide sequence of 16S ribosomal RNA. <4> The composition of the cell wall.

biology