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.

[EX Q]: Question: The ribosomal subunits are formed in the: 
 Options:  <0> Nucleoplasm. <1> Nucleolus <2> Nuclear sheet. <3> Nuclear pore. <4> Cytoplasm.
[EX A]: biology

[EX Q]: Question: The immersion oil used for microscopic observation: 
 Options:  <0> Protects the sample from the oxidizing effect of air. <1> Lubricate the objective lens. <2> Reduces refraction and increases resolution. <3> It acts as a lens that increases magnification. <4> Avoid dehydration of the preparation.
[EX A]: biology

[EX Q]: Question: The atomic mass of carbon is: 
 Options:  <0> The mass of 6.02.1023 carbon atoms, all of them being from the 12C isotope. <1> The mass of 6,022,103 carbon atoms, averaged according to the natural abundance of its isotopes. <2> The twelfth part of the mass of a carbon atom of the 12C isotope. <3> The sum of the mass of 6 protons, 6 neutrons and 6 electrons. <4> The mass of 12 protons.
[EX A]:
chemistry