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: In suppression ion chromatography: 
 Options:  <0> A single column is used and the conductivity of the mobile phase is kept very low. <1> The eluent must be able to be removed selectively after separation and prior to the conductometric measurement. <2> The eluent incorporates a regenerating solution of strong acid flowing in the same direction as the mobile phase. <3> Weak exchangers are used from polystyrene polymers. <4> A mobile phase with ionic conductivity gradient is used.

A: chemistry
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Q: Question: In the synthesis of DNA, the quinolones act: 
 Options:  <0> Joining the double helix and thus blocking the progress of the replication fork. <1> Interlacing in the double helix and thus causing errors in the transcription. <2> On DNA gyrase. <3> As nucleotide analogs that are incorporated into DNA. <4> About DNA polymerases.

A: biology
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Q: Question: Which of the following types of receptors is found in both the sympathetic and parasympathetic ganglia of the vegetative nervous system? 
 Options:  <0> Nicotinics <1> Muscarinic <2> Beta1-adrenergic. <3> Alpha1-adrenergic. <4> Gabaérgicos.

A:
pharmacology
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