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: Which political office did Levin's co-author of "How to Counter Fake News" hold before becoming Governor of Maryland? Passage 1:Koreans in Vietnam is a community of Vietnam with a population of Korean expatriates along with Vietnamese citizens of Korean ancestry. The population initially came in a military capacity, fighting on both sides of the Vietnam War. After the end of the war, there was little Korean migration or tourism in Vietnam, until the rise of the South Korean economy and the decline of the North resulted in an influx of South Korean investors and North Korean defectors, as well as South Korean men seeking Vietnamese wives. As of 2011, according to statistics of South Korea's Ministry of Foreign Affairs and Trade, they numbered roughly eighty thousand people, making them the second-largest Korean diaspora community in Southeast Asia, after the Korean community in the Philippines, and the tenth-largest in the world. A more recent estimate from Vietnam Television says their population might be as large as 130,000.
 Passage 2:Levin holds several patents in chip design and GPS-based authentication, and has published over 50 scientific papers and policy articles. His work has appeared in Foreign Affairs, Foreign Policy, HuffPost, Politico.com, and the Obama White House website. "How to Counter Fake News," an article Levin co-authored with former Governor of Maryland Martin O'Malley, was included in Foreign Affairs's "The Best of 2017" anthology. He has co-authored pieces on cybersecurity with retired General Wesley Clark, and with cybersecurity expert Dan E. Geer Jr.. He also wrote an article with former Under Secretary of Defense for Policy Michèle Flournoy that encourages the Federal Government to embrace practices that protect data and personal identity from the inside out. He recently collaborated with General H. Hugh Shelton and Stephen Ondra on a report that urges the Department of Defense to choose an open source electronic health record when reforming the Military Health System.
 Passage 3:Martha Jones is a fictional character played by Freema Agyeman in the long-running British science fiction television series Doctor Who and its spin-off series, Torchwood. She is a companion of the Tenth Doctor in Doctor Who, after Rose Tyler (Billie Piper). According to the character's creator and executive producer Russell T Davies in his non-fiction book , the character was developed from the beginning with the intention of appearing for a whole of the 2007 series, and to later make guest appearances in subsequent series and crossover appearances in the show's two spin-offs; Martha subsequently made guest appearances in Torchwood series two and in Doctor Who series four in 2008 and special episode The End of Time in 2010. Martha was also intended to make guest appearances in the 2009 series of Torchwood and The Sarah Jane Adventures, but could not due to the actress's other work commitments.

A:
2