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.

Question: When did construction begin on the dam that formed the  Flaming Gorge Reservoir? Passage 1:Natal was born into a family with strong ties to the local politics. His maternal uncle, Javier Albelo Matos, served as a candidate for the mayorship of Ciales the 2000 general election, while his paternal grandfather was an activist for the Partido Popular Democratico (PPD). He studied at Colegio Espíritu Santo in Hato Rey, where he was president of the Student Council. Natal obtained a bachelor's degree from Cornell University in 2008, where he was president of the Puerto Rican Student Association. He did not expect to be accepted by the institution, having applied to study in it as a protocolary measure. When the acceptance letter was received, Natal was surprised and this event triggered a period of adaptation. He offered a speech at his graduation in his role of class president. After returning to Puerto Rico, Natal received a juris doctor from the University of Puerto Rico School of Law in 2011, also serving as president of the student council during his tenure. After graduating from Cornell, Natal became a key figure in a series of strikes held at the University of Puerto Rico in protest of a quota being introduced to the students. Consequently he became involved with the Popular Democratic Party and participated in an internal election for the presidency of the party's National Youth organization. After completing his juris doctor Natal opened his own lawfirm and worked for Charlie Hernández and Luis Vega Ramos, prominent members of the free association movement. In 2013, Natal was named director of the House of Representatives of Puerto Rico Commission on the Judiciary.
 Passage 2:It rises in western Wyoming, in northern Sublette County, on the western side of the Continental Divide in the Bridger–Teton National Forest in the Wind River Range. It flows south through Sublette County and western Wyoming in an area known as the Upper Green River Valley, then southwest and is joined by the Big Sandy River in western Sweetwater County. At the town of La Barge, it flows into Fontenelle Reservoir, formed by Fontenelle Dam. Below there, it flows through open sage covered rolling prairie where it is crossed by the Oregon, California and Mormon emigration trails and then further south until it flows past the town of Green River and into the Flaming Gorge Reservoir in Southwestern Wyoming, formed by the Flaming Gorge Dam in northeastern Utah. Prior to the creation of the reservoir, the Blacks Fork joined the Green River south of Green River, today the mouth of Blacks Fork is submerged by the reservoir.
 Passage 3:In 1817, while still a student, Mickiewicz, Tomasz Zan and other friends had created a secret organization, the Philomaths. The group focused on self-education but had ties to a more radical, clearly pro-Polish-independence student group, the Filaret Association. An investigation of secret student organizations by Nikolay Novosiltsev, begun in early 1823, led to the arrests of a number of students and ex-student activists including Mickiewicz, who was taken into custody and imprisoned at Vilnius' Basilian monastery in late 1823 or early 1824 (sources disagree as to the date). After investigation into his political activities, specifically his membership in the Philomaths, in 1824 Mickiewicz was banished to central Russia. Within a few hours of receiving the decree on 22 October 1824, he penned a poem into an album belonging to Salomea Bécu, the mother of Juliusz Słowacki. (In 1975 this poem was set to music in Polish and Russian by Soviet composer David Tukhmanov.) Mickiewicz crossed the border into Russia about 11 November 1824, arriving in Saint Petersburg later that month. He would spend most of the next five years in Saint Petersburg and Moscow, except for a notable 1824 to 1825 excursion to Odessa, then on to Crimea. That visit, from February to November 1825, inspired a notable collection of sonnets (some love sonnets, and a series known as Crimean Sonnets, published a year later).
2