Instructions: In this task, you are given a multiple-choice question about healthcare. Answer the question based on your information and classify your answers into '1', '2', '3', and '4'.
Input: Question: The water used in the preparation of medicated syrups must:
Options: <1> Be sterile <2> Be purified or distilled water. <3> It is highly recommended that it contain dissolved carbon dioxide. <4> Contain dissolved calcium ions. <5> Contain an adequate proportion of magnesium ions.
Output:
2