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: Washington (CNN) -- President Barack Obama used a Memorial Day ceremony to say it is time for America to properly welcome home Vietnam veterans and show them and their families the respect and gratitude they deserved but didn't receive decades ago. "You came home and sometimes were denigrated when you should have been celebrated," Obama said beneath a scorching sun at the Vietnam Veterans Memorial. "It was a national shame, a disgrace that should have never happened. That's why here today, we resolve that it will not happen again." The event, which launched a 13-year Vietnam War 50th anniversary commemoration, was the culmination of a day of somber events on the annual holiday honoring America's war dead.NEW: President Obama calls the denigration of Vietnam veterans a "national shame""America will be there for you," Obama tells veterans and their familiesMemorial Day launches a 13-year commemoration of the Vietnam War's 50th anniversaryObama lays a wreath to the fallen at Arlington National Cemetery 
 Question:This year marks the 50th anniversary of the _ deploying a significant military presence in Vietnam.

Answer: America


Question: (CNN) Lionel Messi has been hailed as the greatest ever footballer by his Barcelona teammate Marc-André ter Stegen after the Argentine's match-winning performance against rivals Real Madrid Sunday. After taking a blow to the face which left him bloodied and shaken in the first half, Messi scored Barca's equalizer before netting the 500th goal of his club career -- a last-minute winner in the 3-2 victory over Real. "I think he's the greatest ever, because there's nobody similar to him," German international goalkeeper Ter Stegen told CNN Sport's Alex Thomas. "He loves to play football, he loves to see other people around him playing well. I think he's the best ever because of the talent and the amazing performances he's showing every week."Messi scores 500th Barcelona goalHis winner beats Real Madrid at the BernabéuBarça keeper: "Messi is the greatest ever" 
 Question:And, while many praised the brilliance of _'s contemporary rival Cristiano Ronaldo, others extolled older talents like Frenchman Zinedine Zidane and Brazil's Garrincha.

Answer: Lionel Messi


Question: Washington (CNN) Newt Gingrich released his new book, "Understanding Trump," on Tuesday, sharing insights the former House Speaker says he gleaned both during the Trump campaign and in the first months of his presidency. So in pursuit of "understanding Trump," CNN read the first chapter available online. Here are 10 top takeaways: 1. The foreword is written by none other than Eric Trump. Eric Trump lauds Understanding Trump as an "inside look into possibly the greatest campaign of all time," citing how his father "gained the most primary votes of any GOP candidate in the history of the nation." Eric Trump also took time in his foreword to offer praise for his father, President Donald Trump, slipping in a classic "Make America Great Again" tag line:Understanding Trump provides insights into Trump campaignGingrich says Trump reminds him of Bill Clinton 
 Question:"In a very _-the-businessman way, he said, 'So, what's the bottom line?'.

Answer:
Understanding Trump