Task: Text Categorization
Input (English): Question: Substances that prevent abrupt changes in the pH of a solution by adding an acid or a base to it are called: 
 Options:  <0> Aceto-acetic bodies. <1> Tampons. <2> Hydrogens. <3> Anhydrous. <4> Answers 2 and 3 are the correct ones.
Output (English): nursery