Definition: In this task, you're given a question, a context passage, and four options which are terms from the passage. After reading a passage, you will get a brief understanding of the terms. Your job is to determine by searching and reading further information of which term you can answer the question. Indicate your choice as 'a', 'b', 'c', or 'd'. If you think more than one option is plausible, choose the more probable option to help you answer the question.
Input: Question: What is the oldest city that was chosen for filming Aeon Flux? Passage:The screenplay was written by Phil Hay and Matt Manfredi, and directed by Karyn Kusama. It was based on the animated TV series by Peter Chung, who had a minor role in this film version of his work. In the early stages of production, actress Michelle Rodriguez was considered for the part of Æon. She had previously worked with Kusama in Girlfight. Kusama had originally suggested filming in Brasília, the capital of Brazil, because the 20th-century modern architecture of that city fit with her vision of Bregna. The producers rejected the idea because Brasília lacked the infrastructure and technical expertise to support a major film production. After several cities were scouted, Berlin and Potsdam in Germany were chosen for filming. Berlin had several locations that fit into the organic yet structured world of Æon Flux. The crew gained permission to film in several locations that had never allowed such access before, including the Treptow Crematorium, the Adlershof Trudelturm and Windkanal wind tunnel facility, and the Haus der Kulturen der Welt ("House of the World's Cultures"). Additional locations included the Bauhaus Archive and a dissection theatre built in 1790 to train veterinarians, part of the Berlin animal shelter. It was used as the Handler space. Filming was temporarily suspended for a month during September 2004 while Theron recovered from a neck injury she sustained during stunt-work on the tenth day of shooting. She was hospitalized in Berlin for five days and required about six weeks of physiotherapy to recover.
 Links: a. Berlin b. Girlfight c. Matt Manfredi d. Phil Hay (screenwriter)
Output:
a