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].
One example: 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.
Solution is here: China
Explanation: This is a good example. Based on the passage, any cubs will return to China at the age of two

Now, solve this: (CNN) -- The discovery of a "sophisticated" tunnel between a Mexican eat-in kitchen and two Southern California warehouses led authorities on both sides of the U.S.-Mexico border to arrest at least nine suspects and seize between 20 and 30 tons of marijuana. The Thanksgiving Day find followed an eight-month investigation and came about three weeks after authorities discovered a similar drug tunnel in another warehouse in the Otay Mesa area of San Diego. Between the two incidents, agents in the United States and Mexico seized roughly the equivalent of one marijuana cigarette for each of California's nearly 37 million residents, Drug Enforcement Administration special agent Ralph Partridge said Friday.NEW: Authorities describe a "very sophisticated" drug smuggling tunnelNEW: The tunnel was between a Tijuana eat-in kitchen and two San Diego warehousesNEW: Two people have been arrested in the United States, and at least seven in MexicoThe tunnel is in the same area where agents found another this month 
 Question:Its southern entry was in the kitchen of a stucco _, Mexico, home, which had a garage attached big enough for tractor-trailer trucks.
Solution:
Tijuana