instruction:
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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San Diego (CNN) Twenty-five years ago, Paula Claussen's friend invited her to make the short trip from her home in San Diego, California, across the border to Tijuana, Mexico, to donate clothing to people in need. Claussen didn't expect that day to change the course of her life. The drive took less than an hour, but when they arrived at their destination -- a shantytown on the outskirts of Tijuana -- Claussen couldn't believe her eyes. "I was shocked by the conditions that I saw down there," she said. Families with young children were living in ramshackle homes: The dirt floors turned to mud when it rained. The walls had gaps, allowing tarantulas, rattlesnakes and rats to invade. Many roofs were merely old tarps with holes in them.Paula Claussen visited Tijuana, Mexico, to donate clothing 25 years agoThe poverty she saw inspired her to come back and build better homes for residentsProject Mercy houses replace shacks that often have dirt floors and lack basic amenities 
 Question:The nonprofit has constructed more than 1,250 free homes for people living in _'s most desperate communities.
answer:
Tijuana


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Britons are by far the biggest adopters of contactless payments in Europe as the use of the system continues to climb across the continent, new figures reveal. More than one billion contactless transactions worth €12.6billion took place in Europe over the last 12 months – a three-fold increase when compared to the same period in 2014, according to Visa Europe. Britain is the country with the highest number of contactless transactions, with 52.6million worth more than €330million made in March alone, followed by Poland and Czech Republic, with 49.7million and 13.9million transactions respectively. This rapid growth in the UK was fuelled in part by the launch of contactless payments on Transport for London services last September, Visa Europe said.The UK issues the highest number of contactless cardsBritons made 52.6million transactions worth more than €330million in MarchSome 1.1billion contactless transactions worth €12.6billion were made by Visa cardholders across Europe in the last 12 months 
 Question:_ is a payments technology business owned and operated by member banks and other payment service providers from 37 countries across Europe.
answer:
Europe


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Hong Kong generally gets a bad rap when it comes to infectious diseases. Grabbing headlines during recent bird- and swine-flu outbreaks, its proximity to Mainland China as well as its unenviable status as the worst-affected city during the 2003 SARS outbreak, Hong Kong has been central to several global pandemic fears in recent years. It hasn't even escaped fictional outbreaks -- the 2011 movie "Contagion" had patient zero Gwyneth Paltrow bring back an unwelcome souvenir from a business trip to the city. But this bad biological baggage may come in handy. The unwelcome distinction of being home to over one fifth of the world's SARS cases, and two fifths of the 774 fatalities from SARS meant Hong Kong quickly developed and implemented a very sophisticated disease control and epidemiology infrastructure.Expertise gained in Hong Kong during SARS epidemic helpful in battling MERS virusOver 100 MERS deaths have now been reported as cases spikeHong Kong and Chinese researchers looking at "promising" antibodies as MERS cure 
 Question:"Even though our understanding of MERS is only a slowly evolving one, we can see important differences between it and _," he told CNN via email.
answer:

SARS