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: Given three DNA molecules of the same length (A, B and C) and in the same solvent, but with different richness in terms of G + C content (A: 50%, B: 60%, and C: 75% ), How would your melting temperatures (Tm) be ?: 
 Options:  <0> A> B> C. <1> Being in the same solvent, they would be the same in all three cases. <2> The DNA molecule C would not belong to a thermophilic bacterium, given its lower Tm. <3> C> B> A. <4> You can not know with the information of the statement.
answer:
pharmacology


question:
Question: What do you usually associate with the cataplexy characteristic of narcolepsy? 
 Options:  <0> With sleep paralysis. <1> With intense emotions. <2> With hypnagogic and hypnopompic hallucinations. <3> With daytime sleepiness. <4> With irregular schedules.
answer:
psychology


question:
Question: Which Clostridium genus is a producer of enterotoxin A and cytotoxin B responsible for diarrhea (pseudomembranous colitis) associated with treatment with antimicrobials ?: 
 Options:  <0> Clostridium perfringens. <1> Clostridium difficile. <2> Clostridium botulinum. <3> Clostridium novyi. <4> Clostridium histolyticum.
answer:

pharmacology