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: Friedel-Crafts alkylation reactions lead to products that: 
 Options:  <1> They facilitate diazotization reactions. <2> They facilitate the reactions of formation of ethers. <3> Activate the aromatic ring against other substitutions. <4> They deactivate the aromatic ring against other substitutions. <5> None of the above.

Output: 3


Input: Consider Input: Question: The generation of the cold vapor is a form of introduction of the sample for the atomization that is used in atomic absorption spectrometry (EAA) to analyze: 
 Options:  <1> Lead and Arsenic. <2> Mercury. <3> Elements that have a low vapor pressure at room temperature. <4> Halogens of high molecular weight. <5> Alcalinotérreos.

Output: 2


Input: Consider Input: Question: The arenio ion is a reaction intermediate that is formed in the reactions of: 
 Options:  <1> Electrophilic addition. <2> Electrophilic aromatic substitution. <3> Nucleophilic substitution. <4> Nucleophilic addition. <5> Aromatic nucleophilic substitution.

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
Output: 2


