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: Which of the following substances is used as a catalyst in the Contact Process during the manufacture of sulfuric acid ?: 
 Options:  <1> RuO2. <2> V2O5 <3> Cr2O3. <4> RhO2. <5> PdO.
