In this task, you are given a multiple-choice question about healthcare. Answer the question based on your information and classify your answers into '1', '2', '3', and '4'.

[EX Q]: Question: The technique that stimulates the cerebral cortex by applying electrical pulses through an electromagnetic coil, which is used to treat some disorders such as depression, is called: 
 Options:  <1> Transcranial magnetic stimulation. <2> Intracerebral photo stimulation. <3> Functional magnetic resonance or RMf. <4> Evoked potentials of stimulation. <5> Magnetoencephalography
[EX A]: 1

[EX Q]: Question: Esters can be obtained from carboxylic acids and alcohols, by applying the Fischer esterification reaction in which: 
 Options:  <1> A base is used as a catalyst. <2> A ketone is used as the solvent. <3> A reducing reagent is used. <4> An oxidizing agent is used. <5> Acid catalysis is used.
[EX A]: 5

[EX Q]: Question: The systematic nomenclature rules of the IUPAC give priority as a main function, from among the following functional groups, to: 
 Options:  <1> Amines <2> Carboxylic acids. <3> Nitriles <4> Carboxylic ethers. <5> Aldehydes.
[EX A]:
2