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].

Q: Washington (CNN) North Korea might not be able to reach the U.S. mainland with a nuclear weapon yet, but the political fallout from its claimed hydrogen bomb test is here already. Even before the shockwaves of the 5.1 temblor triggered by Tuesday's test wore off, Hillary Clinton was fighting off a volley of Republican attacks, GOP presidential candidates were talking tough and Donald Trump jumped on a chance to chastise China. The episode was a fresh indication of the challenge that Clinton faces in running for the White House on her record as secretary of state, which makes it impossible for her to escape deficiencies in President Barack Obama's national security legacy.The episode is a fresh indication of the challenge that Clinton faces in running for the White House on her record as secretary of stateWashington has tried punishment and inducements repeatedly with North Korea and has failed to change its calculations 
 Question:He then toughened his stance by including _ in his "axis of evil."

A: North Korea
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Q: (CNN) After a slow start in October, flu season in the United States is gaining speed, particularly in the South. Flu activity, which has been increasing since the start of November, is now higher than usual for this time of year, according to a report published Thursday by the Centers for Disease Control and Prevention. Flu is a contagious, viral illness that causes mild to severe symptoms that, in rare cases, can lead to death. Seven children have died, and an additional 856 flu-related hospitalizations have occurred as of December 2, according to the CDC's weekly surveillance report. "Flu is increasing. We're seeing a pretty steep increase in influenza activity across the US but especially in the South," said Brendan Flannery, a co-author of the new report and an epidemiologist in the CDC's flu division.Flu activity is higher than usual for this time of year, CDC saysLouisiana, Mississippi and South Carolina report the highest activitySeven children have died, and there have been 856 hospitalizations 
 Question:Her advice includes the _ recommendation to get a flu shot, but she also adheres to low-tech techniques of contagious disease prevention: "good hand-washing techniques, teaching kids not to share their germs, staying home when you're sick and disinfecting common surfaces," she said.

A: CDC
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Q: Houston (CNN) -- Aviation fans have already named it Dreamliner 2.0. No longer grounded for safety concerns, Boeing's embattled 787 Dreamliner now has a few things to prove. Monday might be a good day to start. That's when domestic Dreamliner flights return to America's airways. At 11 a.m., United Flight 1 is scheduled to depart Houston's George Bush Intercontinental Airport for Chicago's O'Hare International Airport. The airline plans to roll out additional 787 flights throughout the week. Some international carriers have already resumed Dreamliner service. For aviation enthusiasts it's kind of a big deal. As word spreads of Dreamliner's return, travel advisers report they're getting calls from curious fliers looking to connect with one of United's six 787s at Dreamliner hubs.United Flight 1 is the first U.S. commercial Dreamliner flight in more than four monthsBattery troubles led the FAA to ground the 787, the first model fleet grounded in 30 yearsExperts say plane is safe; travel advisers say enthusiasts are requesting bookingsIt's the first of a new generation of efficient airliners that can carry 200-plus passengers 
 Question:Most aren't worried about flying the 787, but if _ develops another problem "then that might change things."

A:
787 Dreamliner
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