Definition: 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: Calcium hydroxide: 
 Options:  <1> It is prepared by adding water to calcium oxide. <2> It is a compound of intense red color. <3> It crystallizes when heated. <4> In solution it remains unchanged in air for months. <5> It is used to paint after neutralizing with HCl.
