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: Which of the following is currently the only contraindication for conservative surgical treatment in breast cancer? 
 Options:  <0> Prior radiotherapy. <1> Tumor of 4 cm. <2> Axillary metastasis. <3> Multifocal tumor <4> Pregnancy of 32 weeks.
[A]: medicine


[Q]: Question: The fear or belief of suffering an important disease, which arises in the subject from the erroneous interpretation of their bodily symptoms, is the nuclear characteristic of: 
 Options:  <0> The conversion disorder. <1> Hypochondria. <2> Panic disorder <3> The Depression <4> Somatization
[A]: psychology


[Q]: Question: Ethidium bromide is a molecule that has a very low fluorescence yield in solution. However, its quantum yield increases remarkably when: 
 Options:  <0> It is atomized. <1> It is interspersed between consecutive base pairs of the DNA double helix. <2> The aqueous solution containing it is oxygenated. <3> It binds to a heavy metal forming a complex. <4> It is oxidized by the action of the enzyme glucoxaoxidase.
[A]:
chemistry