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: Polarography is an analytical technique that refers to: 
 Options:  <1> The absorption of electromagnetic radiation. <2> The emission of electromagnetic radiation. <3> The voltametry with mercury electrode. <4> The use of palladium as a reference electrode. <5> To the potential of asymmetry.
