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: Consider Input: Question: Which of the following gases is the most abundant in the alveolar air? 
 Options:  <1> Oxygen. <2> Carbon dioxide <3> Water vapor. <4> Carbon monoxide. <5> Nitrogen.

Output: 5


Input: Consider Input: Question: Separations by capillary zone electropheresis (CZE) are characterized in that the electrophoretic medium: 
 Options:  <1> It is always formed by 1.0 M HCl. <2> It is always formed by NH3 1.0 M. <3> It is homogeneous throughout the capillary. <4> It is not homogeneous throughout the capillary. <5> It has a pH gradient throughout the entire capillary.

Output: 3


Input: Consider Input: Question: When performing the Ames test, what result would reveal that the compound is a mutagen? 
 Options:  <1> Abnormal division in mouse uterus cells. <2> Abnormal growth in mouse. <3> Proliferation of a hamster ovary cell culture. <4> Reversal in the growth characteristics of Salmonella. <5> No option is correct.


Output: 4