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.
Q: Question: What types of planes did the Australian Flying Corps use the year Holden volunteered for them? Passage 1:"Where the Dream Takes You" is a "tender" pop power ballad with contemporary R&B, soul and lite rock influences, performed in an urban contemporary style. According to the song's official sheet music, published by Walt Disney Music Publishing on Musicnotes.com, "Where the Dream Takes You" is set in signature common time and performed at a moderate tempo of 88 beats per minute in the key of C major. The Disney Song Encyclopedia author Thomas S. Hischak believes that the song's lyrics are "about following your heart to find your true self", which begin "They'll try to hold you back, they will say you're wrong, but they will never understand, no, the journey that you're on." A writer for Barnes & Noble agreed that, thematically, the single "correlates to the film's tale of an inexperienced young adventurer", Milo Thatch, and its diverse cast of supporting characters, all of whom long to follow various dreams of their own as they search for Atlantis. One of its verses reads, "There's something in your soul/That won't be denied/It's the faith to dream that keeps the dream alive/So you still believe and you know you must go", encouraging listeners to follow their dreams despite others' opinions. Lasting a duration of four minutes, AllMusic cites the song's mood as both "earnest" and "mellow"; Mýa performs it using a "sweet vocal", which spans two octaves from G3 to D♭5. Based on a melody heard only briefly during the film, "Where the Dream Takes You" encompasses "soft, contemporary beats" combined with the singer's "dulcet tones" that recall music played in a piano lounge, contrasting with the time period in which the film itself is set. Its production, which has been described as "polished", was handled by Jay Selvester, Robbie Buchanan and Ron Fair.
 Passage 2:The ruins of the Norman Canterbury Castle and St Augustine's Abbey are both open to the public. The medieval St Margaret's Church now houses "The Canterbury Tales", in which life-sized character models reconstruct Geoffrey Chaucer's stories. The Westgate is now a museum relating to its history as a jail. The medieval church of St Alphege became redundant in 1982 but had a new lease of life as the Canterbury Urban Studies Centre, later renamed the Canterbury Environment Centre; the building is used by the King's School. The Old Synagogue, now the King's School Music Room, is one of only two Egyptian Revival synagogues still standing. The city centre contains many timber-framed 16th and 17th century houses, however there are far fewer than there were before the Second World War, as many were damaged during the Baedeker Blitz. Many are still standing, including the "Old Weaver's House" used by the Huguenots. St Martin's Mill is the only surviving mill out of the six known to have stood in Canterbury. It was built in 1817 and worked until 1890; it is now a house conversion. St Thomas of Canterbury Church is the only Roman Catholic church in the city and contains relics of Thomas Becket.
 Passage 3:Holden enlisted in the Australian Imperial Force on 26 May 1915, and was posted to the 4th Light Horse Brigade as a private. He departed for Egypt aboard the transport A29 Suevic on 13 June. Serving as a driver first in the Middle East and then on the Western Front, his mechanical ability and sense of adventure led him to volunteer for the Australian Flying Corps (AFC) in December 1916. After qualifying as a pilot in England, he was commissioned a lieutenant and posted to No. 2 Squadron. Commanded by Major Oswald Watt, No. 2 Squadron's personnel included many former Lighthorsemen, as well as mechanics from the AFC's first combat formation, the Mesopotamian Half Flight. The force trained extensively in England commencing in January 1917, before deploying to the Western Front that September. Holden was involved in the AFC's first day of combat in France; just after noon on 2 October, in the vicinity of Saint-Quentin, he and his wingman engaged a German two-seater that managed to escape.

A:
3