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In this task, you will be presented with a passage and have to answer a question based on your understanding of the events inferred from the passage. Try to find the best answer that is most likely to fill in "_". Note that the URLs in the text have been replaced with [Link].
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Rio Ferdinand believes Louis van Gaal's decision to return Wayne Rooney to his favoured attacking role has led to the Manchester United's upturn in performance levels. Writing in his column in The Sun ahead of the Manchester derby on Sunday, Ferdinand, now at Queens Park Rangers, revealed his belief that Rooney playing as a striker is fundamental to United hitting fifth gear. He praised Van Gaal for moving his captain further up the field after a spell in the centre of the pitch at the start of the year but admitted the return to form and fitness of Ander Herrera, Marouane Fellaini and Michael Carrick has also been important.Rio Ferdinand says Manchester United need Wayne Rooney in attackHe believes Rooney's form has been key to their upturn in performancesFerdinand said United's 2-1 win at Anfield shows they are 'on to something'Manchester United vs Manchester United: The expert view of the derbyCLICK HERE for all the latest Manchester United news 
 Question:Ferdinand also pointed to the return of midfield player Michael Carrick (left) as a help to _.
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Manchester United


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Rio de Janeiro (CNN) A showcase of Brazilian culture will wrap up the 2016 Summer Olympic Games in Rio Sunday with the staging of the closing ceremony at Maracana Stadium. Organizers said more than 41,000 tickets have been sold for the event but there are still spots available, ranging from 600 reais to 3,000 reais ($187 to $936 USD). Most of the details are being kept under lock and key, but organizers have released some information about the giant party. Rosa Magalhaes, the creative director for the closing ceremony, said it will be a festive atmosphere with a touch of melancholy.Closing ceremony begins Sunday at 7 p.m. ET12,000 volunteers will take partBrazil's acting President will not participate 
 Question:Magalhaes noted that while the _ is a great venue, it does present some challenges for the creative team, especially when trying to recreate the big samba floats that Rio's carnival is known for.
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Maracana Stadium


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Satellite data show people are overdrawing water from some of the world's largest groundwater basins. Researchers from the University of California, Irvine say it's unclear how much water is left in the most overburdened aquifers. The problem is expected to worsen with climate change and population growth. The Arabian Aquifer System, an important water source for more than 60 million people, is the most overstressed in the world. The Indus Basin aquifer of northwestern India and Pakistan is the second-most overstressed, and the Murzuk-Djado Basin in northern Africa is third. California's Central Valley, used heavily for agriculture and suffering rapid depletion, was slightly better off, but was still labeled highly stressed in the first study.Arabian Aquifer System, an important water source for more than 60 million people, is the most overstressed in the worldResearchers say it's unclear how much water is left in most hard hit aquifers 
 Question:The farm-rich _ in California was considered highly stressed.
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Central Valley