During her trip to Washington this week, Nobel Peace Prize nominee Malala Yousafzai met President Barack Obama, first lady Michelle Obama, and their daughter Malia Obama in the Oval Office. The White House/Getty Images hide caption

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A United Nations vehicle carrying inspectors from the Organization for the Prohibition of Chemical Weapons (OPCW) leaves a hotel in Damascus, on Wednesday. Some 19 OPCW arms experts are in Syria and have started to destroy weapons production facilities. Louai Behara/AFP/Getty Images hide caption

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Malala Yousafzai, 16, speaks in New York last month. Yousafzai was shot a year ago by the Taliban for her outspoken advocacy in favor of girls' education in Pakistan. She is considered one of the favorites for the Nobel Peace Prize, which will be announced Friday. Ramin Talaie/Getty Images hide caption

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European Commission President Jose Manuel Barroso of Portugal during today's Nobel Peace Prize ceremony in Oslo. Nigel Waldron/Getty Images hide caption

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If the Nobel Peace Prize is to go to someone involved with the Arab Spring, it may be difficult to choose who gets the award. Here, men celebrate in Tunis after President Zine El Abidine Ben Ali said he would not seek another term.

Fethi Belaid/AFP/Getty Images hide caption

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