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.

Input: Consider Input: Question: Controls the passage of substances to the central nervous system: 
 Options:  <0> Meninges. <1> Choroid plexus. <2> Hemato-encephalic barrier. <3> White substance <4> Schwann cells and oligodendrocytes.

Output: biology


Input: Consider Input: Question: The 2,4-diaminopteridine systems, such as aminopterin or methotrexate, are good antitumor agents since they reduce the biosynthesis of purines and pyrimidines by inhibiting the enzyme: 
 Options:  <0> Timidylate synthetase <1> Aromatase <2> Topoisomerase <3> Reverse transcriptase <4> Dihydrofolate reductase.

Output: pharmacology


Input: Consider Input: Question: Reactions that use copper (I) salts as reagents to replace the nitrogen in the diazonium salts are called reactions of: 
 Options:  <0> Sandmeyer <1> Chichibabin <2> Peterson. <3> Gabriel. <4> Diels-Alder.


Output: chemistry