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: It is a genus of strict anaerobic bacteria that produce endospores and that contain pathogenic species: 
 Options:  <0> Bacteroides. <1> Bacillus. <2> Clostridium <3> Corynebacterium <4> Mycobacterium

A: biology
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Q: Question: At what stage is the person when they begin to balance the positive and negative consequences of drug use and, as a result, begin to consider stopping consumption, but basically maintain their ambivalence in this decisional balance? 
 Options:  <0> Stadium of action. <1> Contemplation stadium. <2> Relapse stadium. <3> Pre-contemplation stadium. <4> Post-relapse stadium.

A: psychology
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Q: Question: In the kinetic methods of analysis: 
 Options:  <0> Slow reactions can be used. <1> It is necessary that the reaction be completed in order to obtain the data of the equilibrium concentrations. <2> Low concentrations of a catalyst can be determined as long as the speed of the reaction does not depend on the concentration thereof. <3> It is not necessary to rigorously control the experimental conditions. <4> Mixtures of analytes can be determined as long as they all react with the same reagent at the same reaction rate.

A:
chemistry
****