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: Immunoglobulin isotype change affects: 
 Options:  <0> The constant regions of the heavy chains. <1> The constant regions of the light chains. <2> The totality of heavy chains. <3> The entire immunoglobulin molecule. <4> The hypervariable regions of the heavy chains.

A: biology
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Q: Question: In the monocompartmental model, the shock dose for a drug that follows linear kinetics is administered in multiple doses orally and absorbed extraordinarily quickly; It can be calculated as: 
 Options:  <0> The ratio between the maintenance dose and the dosage interval. <1> The product of the maintenance dose by the rate constant of absorption. <2> The quotient between the dosing interval and the absorption rate constant. <3> The product of the maintenance dose by the accumulation factor. <4> The product of the dosing rate by the absorption rate constant.

A: pharmacology
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Q: Question: The reaction product of cyclohexanone with bromine catalyzed by a base is: 
 Options:  <0> 2-Bromocyclohexanone. <1> 2,2-Dibromocyclohexanone. <2> 2,2,6-Tribomociclohexanona. <3> 1,1-Dibromocyclohexane. <4> 2,2,6,6-Tetrabromocyclohexanone.

A:
chemistry
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