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 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.

A: biology
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Q: Question: Among other properties with respect to hypericin we can indicate: 
 Options:  <0> It is a powerful hepatoprotector extracted from the roots of Hypericum perforatum. <1> It is a powerful cholagogue that is extracted from the resin of the Hypericum perforatum rhizome. <2> It is a removable antiretroviral of the aerial parts of Hypericum perforatum. <3> It is a laxative that is extracted from the leaves of Hypericum perforatum. <4> It is a potent hepatoprotective present in the fruits of Hypericum perforatum.

A: pharmacology
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Q: Question: Which of the following is a poor prognostic factor in acute lymphoblastic leukemia ?: 
 Options:  <0> Age 1-9 years. <1> Phenotype B. <2> Karyotype with translocation 9; 22. <3> Leucocytosis of 25,000 / microL. <4> Hyperploid DNA index.

A:
pharmacology
****