Definition: In this task, you're given a question, along with three passages, 1, 2, and 3. Your job is to determine which passage can be used to answer the question by searching for further information using terms from the passage. Indicate your choice as 1, 2, or 3.
Input: Question: How many key steps are in the ribosomal protein synthesis? Passage 1:Barry Allen's first appearance on The Flash is in the episode "Pilot". Barry is introduced as quite a goofy and kind character, who is quite brilliant at his job as a crime scene investigator for the Central City Police department. His obsession for the particle accelerator and interest in Harrison Wells began before his superhuman abilities. After the explosion that consequently led to Barry being struck by lightning, he wakes up and discovers that he has developed meta-human abilities, in particular the power of speed. This season portrays Barry's development in his superpowers, he has his setbacks in the beginning, in "Fastest Man Alive" he begins fainting, which he only finds out later that it is because his body is burning more energy than he could intake. Throughout the episode, Barry's character develops and he is able to better control his powers through training at the S.T.A.R Labs, with his team the STAR team: Caitlin Snow, Cisco Ramon and Harrison Wells. Barry's once platonic (at least to Iris West) relationship with Iris is turned complicated after all the episode "The Man in the Yellow Suit" when Barry confesses his love to her. In the episode "Crazy for You" however, Barry begins a relationship with Linda Park, who in the next episode suspects that Barry is still in love with Iris West. Over the course of the second half of the season, Barry begins to suspect and learns that Wells is actually the man in the yellow suit that killed his mother, otherwise known by his true name Eobard Thawne, whom had been manipulating events since that night to turn Barry into The Flash in an effort to harness his speed and return to the future. Eobard ultimately fails and is erased from existence by his distant ancestor, Eddie Thawne when Eddie kills himself. This provides an effort to allow Barry to travel to the past and save his mother. However, doing so results in a singularity opening above Central City which Barry then has to stop.
 Passage 2:Split-intein circular ligation of peptides and proteins (SICLOPPS) is a biotechnology technique that permits the creation of cyclic peptides. These peptides are produced by ribosomal protein synthesis, followed by an intein-like event that splices the protein into a loop. By contrast with the nonribosomal peptide synthetases that produces some cyclic peptides like gramicidin S, SICLOPPS offers the advantage that the peptides' structure can be encoded by DNA in a simple manner according to the genetic code, but for this reason it imposes limitations on the types of amino acids incorporated that are comparable to those that apply to ordinary proteins. As implemented there is also some constraint on the peptide sequence of the cyclic sequence; for example, libraries may use the sequence SGXX..XXPL to increase the efficiency of circularization of the peptide. SICLOPPS is frequently used with a library of randomized DNA sequence that permits the simultaneous production and screening of large numbers of constructs at once, followed by the recovery of the DNA sequences responsible for the activity of the clone of interest.
 Passage 3:About 460, Roman diplomat and bishop Sidonius Apollinaris sent a letter to Riothamus asking his help to quell unrest among the Brettones, British colonists living in Armorica; this letter still survives. In the year 470, Western Emperor Anthemius began a campaign against Euric, king of the Visigoths who were campaigning outside their territory in Gaul. Anthemius requested help from Riothamus, and Jordanes writes that he crossed the ocean into Gaul with 12,000 soldiers. The location of Riothamus' army was betrayed to the Visigoths by Arvandus, the jealous praetorian prefect of Gaul, and Euric defeated him in the Battle of Déols after Riothamus army was driven from Avaricum (Bourges) where he had been welcomed by the Bituriges before the fight. Riothamus was last seen retreating northward to Burgundy when Euric besieged Arvernum (Clermont-Ferrand) just south of the Bituriges territory.

Output:
2