Q: 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: Who did the mother of the reigning queen marry that allowed her to serve as regent? Passage 1:Ptacek was born in East Berlin to a family of Czech and German descent. His family fled East Germany for the United States when he was five years old. They eventually settled in Chicago, where young Ptacek was first exposed to blues music. He moved to Tucson in the early 1970s, where he began his own musical career, most often solo, but sometimes he plugged in and led a trio as Rainer & Das Combo. He co-founded Giant Sandworms with Howe Gelb in the late 1970s. When the band decided to move to New York and became Giant Sand, Ptacek opted to stay in Tucson to make sure that he would not disrupt his then-new family. Although he never became well known in the United States, he became more and more recognized in Europe. ZZ Top guitarist Billy Gibbons was so impressed with the singer-guitarist that he arranged to have Kurt Loder review Ptacek's "Mush Mind Blues" cassette in Rolling Stone. Ptacek later traveled to Houston at the invitation of Billy Gibbons to record at Gibbons' Gold Star Sound Services studio which saw release as "The Texas Tapes" meeting international attention and approval. Robert Plant, similarly impressed, flew Ptacek to England for the sessions for B-sides to supplement the singles from Fate of Nations.
 Passage 2:When Isabella first became queen, she was only three years old. The queen mother, Maria Christina of the Two Sicilies, served as regent. The first and foremost political division of the Isabeline era was between Carlists and Cristinos (or Isabelinos), the former being supporters of Infante Carlos, Count of Molina, a rival claimant to the throne and the latter being supporters of Maria Christina and Isabella. The former supported absolute monarchism and the traditionalism of the Antiguo Régimen ("Old Regime"); they were uniformly close to the Roman Catholic Church, and generally clericalist. The latter were generally supporters of constitutional monarchy (although some, including Maria Christina herself, were more inclined toward enlightened absolutism); they were liberals of one stripe or another, ranging from liberal conservatives and those whose liberalism was strictly economic to social liberals. In the 1830s, these two groups faced off in the First Carlist War, which the Cristinos won. The terms of surrender—notably the Convention of Vergara—left an opportunity for relatively moderate Carlists to continue to play a role in the country's politics, and many did so over the ensuing decades.
 Passage 3:Secretary of State for Employment and Productivity Barbara Castle introduced an Employed Persons (Health and Safety) Bill in 1970 but the debate around the Bill soon generated a belief that it did not address fundamental issues of workplace safety. In the same year, the Occupational Safety and Health Act was passed into United States federal law. As a result, a committee of inquiry chaired by Lord Robens was established towards the end of Harold Wilson's first government. When the Conservative Party came to power following the 1970 United Kingdom general election, they gave Castle's Bill no parliamentary time, preferring to wait for the Robens Report which was published in 1972. Conservative Secretary of State for Employment William Whitelaw introduced a new Bill on 28 January 1974 but Labour were returned to power in the February 1974 United Kingdom general election and the Bill again lost. The new Labour administration finally secured the passage of a Bill that year.

A:
2