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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Question: We're not bluffing, the Obama administration told Afghanistan on Tuesday in announcing for the first time it has started planning for the possible withdrawal of all U.S. troops by the end of the year if no security agreement is signed. Statements by the White House and Defense Secretary Chuck Hagel showed President Barack Obama's impatience with Afghanistan President Hamid Karzai's refusal to sign the agreement that would keep several thousand American troops in the country after combat operations conclude this year. In a phone call with Karzai on Tuesday to discuss upcoming elections for a new Afghan leader, Obama made clear that time was running out to properly plan for keeping any U.S. forces in the country beyond 2014, the White House said.President Obama calls Afghan leader to discuss security agreementObama orders planning for bringing home all U.S. troops at the end of 2014Afghan President Karzai refuses to sign a deal to keep some troops thereThe White House says an agreement could happen after Karzai leaves office in April 
 Question:Obama, he said, has been very clear that the possibility of U.S. troops staying in Afghanistan depends "on whether we have a bilateral security agreement signed by the Afghani government, to assure our rights of our troops and other important elements that are required any time _ has troops in another country."

Answer: U.S.


Question: Cristiano Ronaldo dominates Wednesday's front pages in Spain with both AS and Marca leading on his fourth golden boot for having been crowned Europe's top goalscorer during the 2014-15 season. The Real Madrid star is quoted as saying in AS that he is now targeting a fifth and sixth accolade over the next two campaigns, and who would bet against him achieving the feat. Portuguese daily A Bola certainly seem to think the jewel in their crown is capable of doing so, with Ronaldo quoted on their front page as saying, 'I can still be better!' claiming he is yet to fulfill his ambition.Cristiano Ronaldo is eulogised by the Spanish and Portuguese pressReal Madrid forward collected a fourth golden boot as Europe's top scorerBarcelona are willing to sell Sandro with a buy-back clause this JanuarySpanish media report that two Premier League clubs will table offersTottenham manager Maurico Pochettino is leading the chase for forward 
 Question:Elsewhere, Tottenham will be looking to further strengthen their attacking options this January transfer window by tabling an offer for Barcelona misfit _, according to reports in Spain.

Answer: Sandro


Question: Port-au-Prince, Haiti (CNN) -- Earthquake victims, writhing in pain and grasping at life, watched doctors and nurses walk away from a field hospital Friday night after a Belgian medical team evacuated the area, saying it was concerned about security. The decision left CNN Chief Medical Correspondent Sanjay Gupta as the only doctor at the hospital to get the patients through the night. CNN initially reported, based on conversations with some of the doctors, that the United Nations ordered the Belgian First Aid and Support Team to evacuate. However, Belgian Chief Coordinator Geert Gijs, a doctor who was at the hospital with 60 Belgian medical personnel, said it was his decision to pull the team out for the night. Gijs said he requested U.N. security personnel to staff the hospital overnight, but was told that peacekeepers would only be able to evacuate the team.NEW: Belgian team chief says he decided to leave when U.N. could not provide securityDoctors and nurses return to field hospital Saturday morningThe only doctor present overnight was CNN's Sanjay GuptaTeam has security in place and plans to stay Saturday night 
 Question:_ -- assisted by other CNN staffers, security personnel and at least one Haitian nurse who refused to leave -- assessed the needs of the 25 patients, but there was little they could do without supplies.

Answer:
Sanjay Gupta