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: How long had the United Nations been in existence when Gross was appointed? Passage 1:On October 11, 1949, United States Secretary of State Dean Acheson appointed Gross as the United States' deputy delegate to the United Nations. Only two months later, the chief delegate, Warren Austin, took a leave of absence, and Gross took over as acting head of the U.S. delegation to the U.N. The major issue facing the United Nations at that time was the Soviet Union's proposal that, with the conclusion of the Chinese Civil War, the Communist People's Republic of China should replace the Republic of China on the United Nations Security Council. On January 13, 1950, the Soviet delegate, Jacov Malik, walked out of the Security Council in protest. Malik remained absent for several months, and as such the Soviet Union failed to exercise its veto power to block United Nations Security Council Resolution 82, which condemned North Korea at the beginning of the Korean War; on behalf of the U.S., Gross voted in favor of the resolution. In fall 1950, Warren Austin returned from his leave of absence, and Gross continued to serve as Austin's deputy until 1953.
Passage 2:In 1908, she met John Dailey de Angeli, a violinist, known as Dai. They were married in Toronto on April 12,1910. The first of their six children, John Shadrach de Angeli, was born one year later. After living in many locations in the American and Canadian West, they settled in the Philadelphia suburb of Collingswood, New Jersey. There in 1921 Marguerite started to study drawing under her mentor, Maurice Bower. In 1922, Marguerite began illustrating a Sunday School paper and was soon doing illustrations for magazines such as The Country Gentleman, Ladies' Home Journal, and The American Girl, besides illustrating books for authors including Helen Ferris, Elsie Singmaster, Cornelia Meigs, and Dorothy Canfield Fisher. Her last child, Maurice Bower de Angeli, was born in 1928, seven years before the 1935 publication of her first book, Ted and Nina Go to the Grocery Store. The de Angeli family moved frequently, returning to Pennsylvania and living north of Philadelphia in Jenkintown, west of Philadelphia in the Manoa neighborhood of Havertown, on Carpenter Lane in Germantown, Philadelphia, on Panama Street in Center City, Philadelphia, in an apartment near the Philadelphia Art Museum, and in a cottage in Green Lane, Pennsylvania. They also maintained a summer cabin on Money Island in Toms River, New Jersey. Marguerite's husband died in 1969, eight months before their 60th wedding anniversary.
Passage 3:The Tremp Basin evolved into a sedimentary depression with the break-up of Pangea and the spreading of the North American and Eurasian Plates in the Early Jurassic. Rifting between Africa and Europe in the Early Cretaceous created the isolated Iberian microplate, where the Tremp Basin was located in the northeastern corner in a back-arc basin tectonic regime. Between the middle Albian and early Cenomanian, a series of pull-apart basins developed, producing a local unconformity in the Tremp Basin. A first phase of tectonic compression commenced in the Cenomanian, lasting until the late Santonian, around 85 Ma, when Iberia started to rotate counterclockwise towards Europe, producing a series of piggyback basins in the southern Pre-Pyrenees. A more tectonically quiet posterior phase provided the Tremp Basin with a shallowing-upward sequence of marine carbonates until the moment of deposition of the Tremp Formation, in the lower section still marginally marine, but becoming more continental and lagoonal towards the top.

A:
1