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].

(CNN) The cavalry is coming! Not exactly, but the sentiment of reassurance is the same. This week, US Defense Secretary James Mattis arrives in Asia to visit South Korea and Japan. Two stalwart US allies, policymakers in both capitals have nevertheless been shaken by statements Donald Trump made while campaigning for President. None of these was more dramatic than the suggestion that these allies should pay more for US troops or risk having these forces withdrawn. Statements like this played to the worst fears in Seoul and Tokyo that the United States might no longer be a committed ally. It is now Mattis' job to reassure them of US commitments and return the trajectory of alliance relations back to pre-2016 presidential campaign rhetoric.Jeffrey Hornung: Japan, South Korea were shaken by statements Donald Trump made while campaigningWashington's alliances with Seoul and Tokyo will be critical in managing challenges posed by China and North Korea, he says 
 Question:Given the severity of the _ threat, it is crucial they hammer out any possible differences that may have arisen since Trump became president.
North Korea

Carrying heavy items to his car and pushing a wheelchair, terror preacher Hani Al-Sibai does not seem to have severe mobility problems. Yet he is claiming £50,000 a year in disability and other benefits as he defies efforts to kick him out of the country. Now Al-Sibai, a ‘key influencer’ of the group behind the Tunisian beach massacre, could have his handouts from the taxpayer slashed after the Mail took these photographs casting doubt on his claim to be severely disabled. Al-Sibai, who has fought deportation from the UK for more than a decade, insists he is too unwell to work, cannot walk without severe discomfort and requires help with basic care, such as washing, dressing and using the toilet.Hani Al-Sibai says he has 'severe mobility problems' to get disability cashBut Al-Sibai was captured on camera by the Mail casting doubt on his claimHate preacher has fought deportation from the UK for more than a decadeThought to be a 'key influencer' behind the Tunisian beach massacre 
 Question:However the photographs caught _-Sibai walking with apparent ease in the sunshine.
Hani Al

(CNN) A former attorney for two of Prince's dead siblings says they revealed Prince had an addiction to Percocet decades before his sudden death in April. Prince's half-brother, Duane Nelson, said he used to get the drug for Prince to help him come down after shows, Michael B. Padden said. "Duane told me that he witnessed him taking the drugs and he also procured Percocet for him," Padden said. Nelson was adamant that Prince was in no way just a recreational user, Padden said. He started using the drug to help him deal with the rigors of performing. Another half-sibling, Lorna Nelson, confirmed Prince's drug use but was not involved in getting drugs for him, Padden said. She died in 2006.Lawyer says Prince's half-brother told him Prince was addicted to Percocet decades agoDay before he died, addiction specialist launched "life-saving mission," lawyer says 
 Question:Authorities have also said the probe into _'s death is a criminal investigation.

Prince