Given the task definition and input, reply with output. 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: Why was Saoirse Ronan replaced by Alicia Vikander? Passage 1:In 2009 it was announced that the feature film Testament of Youth was in development by BBC Films and Heyday Films producer David Heyman, and was to be directed by James Kent. This had the support of the Vera Brittain Estate, Brittain's daughter Shirley Williams, and Brittain's biographer Mark Bostridge who is acting as consultant. Saoirse Ronan was cast to play Brittain in 2012 but was replaced in December 2013 when it was announced that Alicia Vikander would play Vera Brittain in the film which was released in late 2014 as part of the First World War commemorations. On 4 February 2014 Kit Harington joined the cast to play the role of Brittain's fiancé Roland Leighton. On 13 February 2014, Colin Morgan, Taron Egerton, and Alexandra Roach were announced to have joined the film's cast. An ensemble cast was later confirmed as filming began, including Dominic West, Emily Watson, Joanna Scanlan, Hayley Atwell, Jonathan Bailey and Anna Chancellor. It substituted Merton College, Oxford in the scenes showing Brittain's time as a student at Somerville College, arguing that filming in Somerville itself would been too difficult in light of the new buildings constructed there since the film's time period.
 Passage 2:In 2004, Mendler got her first acting role in the animated Indian film The Legend of Buddha, in which she portrayed Lucy. When she was 13 years old, she got an acting role as a guest star on the soap opera General Hospital. She portrayed the dream child of character Lulu Spencer, in which the two have an argument on Mendler's character's birthday. The scene, lasting just under a minute, is later revealed to be a dream. That same year, Mendler was the voice of the character Thorn in the video game Bone: The Great Cow Race, which was based on the Bone comic series. In 2007, Mendler made her film debut in the film adaption of the Alice series, titled Alice Upside Down. Mendler starred alongside Disney Channel actress Alyson Stoner and Lucas Grabeel. Mendler portrayed the antagonistic role of Pamela, who is the rival of Stoner's character, Alice. For the film's soundtrack, Mendler provided backing vocals on the song "Free Spirit", performed by Stoner. Also in 2007 Mendler auditioned for Sonny with a Chance for the role of Sonny Munroe, but Demi Lovato was chosen. In 2008, it was announced that Mendler would play the role of Kristen Gregory in the film adaption of the popular teen novel series The Clique by Lisi Harrison. Mendler had the role of Kristen, a girl who attends OCD on a scholarship, and works hard to keep her good grades.
 Passage 3:He was born John Miller in County Clare, Ireland. His father was John Miller and his mother, John's wife, Anne née Browne. He was educated at Dalston School and Eton College before joining the British Army in 1760 as a cornet. He was on active service in the Battle of Emsdorf and at Belleisle, France in 1761, before retiring from the army in 1763. He was admitted to study at the Middle Temple in 1765, though does not seem to have made any progress with his legal studies. He also studied at Trinity Hall, Cambridge, though he did not graduate. In August 1765 he married Anna née Riggs (1741–1781), adding her name to his own. They had a son and a daughter. In July 1762 he inherited his family estates; they were worth little, but his wife brought substantial wealth to the marriage, enabling him to build a prestigious house at Batheaston, Somerset. The couple there held a fortnightly literary salon along with competitions and prizes. The prizes were drawn from an ornately decorated Roman vase and the affair was mocked as Lady Miller's Vase, though that did not dissuade distinguished contributions from the like of David Garrick and Christopher Anstey. In 1778 he was created a Baronet, of Ballicasey in the County of Clare. Anna died on 24 June 1781; on 9 September 1795 he married Jane née Sell, widow of Sir Thomas Davenport. He was elected Member of Parliament for Newport, Cornwall in 1784.
1