You will be given a definition of a task first, then some input of the task.
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: The folded sheet :
Options: <0> It is formed by a single polypetide chain. <1> It presents a distance between adjacent amino acids of approximately 4 angstroms. <2> It is formed by the union of two or more strands by hydrogen bonds. <3> Presents the side chains of contiguous amino acids pointing to the same side. <4> They are of two types: parallel, where the chains of the sheet go in a different direction and antiparallel, where they go in the same direction.
Output:
chemistry