instruction:
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:
Question: Which of the following statements is correct regarding the epidemiology of mood disorders ?: 
 Options:  <0> Bipolar disorders account for 25-30% of all mood disorders. <1> The average duration of a depressive episode is usually about 2-3 months. <2> The percentage of relapses of depression throughout life is estimated at 75%. <3> The risk of suicide in depressive disorder is greater than bipolar disorder. <4> 50% or more of the history of bipolar disorder is found in the families of patients with depression.
answer:
psychology


question:
Question: Proton pump inhibitor drugs are useful in the treatment of: 
 Options:  <0> Constipation. <1> Corneal ulcer. <2> Peptic ulcer. <3> Traveler's diarrhea. <4> Crohn's disease.
answer:
nursery


question:
Question: Nitric oxide: 
 Options:  <0> It is synthesized from methionine. <1> Activates cAMP-dependent protein kinase (PKA). <2> It binds to receptors coupled to G proteins (GPCR). <3> Induces relaxation of the vascular endothelium. <4> It binds to receptors with protein tyrosine kinase (PTK) activity.
answer:

chemistry