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 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.
biology

Question: If a patient presents a facial paralysis that does not affect the musculature of the forehead we should think that the lesion is: 
 Options:  <0> At the supranuclear level. <1> In the geniculate ganglion. <2> In the stylomastoid foramen. <3> In the pontocerebellar angle. <4> In the internal auditory canal.
medicine

Question: Protein kinase A (PKA): 
 Options:  <0> It induces the synthesis of glycogen in response to an increase in glucagon in the blood. <1> It is a membrane protein that is activated in response to an increase in circulating GTP. <2> It is activated through the cAMP produced in response to an increase in adrenaline in the circulation. <3> It inhibits the lipolysis of triacylglycerides accumulated in adipose tissue, in response to an increase in intracellular cAMP. <4> It is a monomeric protein that inhibits the synthesis of ATP and muscle contraction.

pharmacology