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: The chloride present in a solution can be determined volumetrically, by the Mohr method, using Ag (I) as a reagent. What indicator is used in this assessment ?: 
 Options:  <0> K2Cr2O7. <1> Fe2 (SO4) 3. <2> K2CrO4. <3> KSCN <4> FeSO4.
[A]: chemistry


[Q]: Question: What are the leaders of the Structural / Strategic School of Systemic Therapy? 
 Options:  <0> O'Hanlon and Weiner-Davis. <1> Haley and Minuchin. <2> Weakland and Fisch. <3> Keeney and Ross. <4> Stierlin and Weber.
[A]: psychology


[Q]: Question: It is a stop codon for translation: 
 Options:  <0> AUG. <1> UAU <2> UUU <3> UAC. <4> UAA
[A]:
biology