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].

Example input: For four years we have waited expectantly for the pitter patter of tiny paws. Soon, that wait could finally be over. Tian Tian, the UK's only female giant panda, has conceived and could give birth to a cub as early as August. However Edinburgh Zoo, where the pandas live, have warned people 'not to get too excited' as the process is 'extremely complex'. Moreover, on the two previous occasions keepers inseminated Tian Tian - whose name means 'Sweetie' - she has failed to produce a panda cub. She was artificially inseminated again in March this year, but keepers at the zoo say implantation - when a fertilised egg attaches to the uterus - has not yet occurred.Tian Tian has conceived and could give birth to a cub as early as AugustShe has been inseminated twice before but so far failed to produce a cubTian Tian and Yang Guang arrived in 2011 from China to great fanfareOn loan at £600k a year, became first giant pandas to live in UK for 17 years 
 Questions:Under the terms of the agreement any cubs will return to _ at the age of two, the age at which they would normally leave their mother in the wild.
Example output: China
Example explanation: This is a good example. Based on the passage, any cubs will return to China at the age of two
Q: (CNN) -- Two pirates in Somalia vowed revenge Monday, after the U.S. military killed three pirates and freed a U.S. ship captain who had been held hostage for several days. Crew members of the Maersk Alabama celebrate after hearing the Navy had rescued their captain from pirates. The pirates told a Somali journalist that they were angered by the U.S. action, as well as a French raid Friday that killed two pirates and one hostage and freed four hostages. "We have decided to kill U.S. and French sailors if they happen to be among our future hostages," said Abdullahi Ahmed, a member of a pirate group based at Harardhere, a coastal town in central Somalia.NEW: Obama promises U.S. will confront piracyPirates vow to kill U.S., French mariners if they become hostagesU.S. Navy killed three pirates in rescue of cargo ship captainFrench forces killed two pirates in rescue raid Friday 
 Question:"The killing of our boys was aggression, and the _ will see what they get from their operation," he said.
A:
U.S.