In this task, you will be given a passage, a question and a list of single-word events identified from the passage. The goal is to point out all events from the given event list that can answer the question. If a question is unanswerable or none of the events answer the question, output should be empty.
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Question: Passage: But his latest comments remove any doubt that he also backs revisionist historians -- often branded in the West as neo-Nazis -- who maintain Nazi Germany's systematic slaughter of an estimated six million Jews between 1933 and 1945 never took place. "Why, under the pretext of this massacre, have you come to the heart of Palestine and the Islamic world ..., why have you created an artificial Zionist regime?" Question: What will happen in the future? Events: ['backs', 'branded', 'maintain', 'slaughter', 'come', 'created', 'remove', 'massacre']

Answer: backs

Question: Passage: The western military alliance invited the three central and eastern European countries to join the 16-nation bloc in July 1997 at the Madrid summit. The three countries have finished all necessary formalities for accession after the Hungarian parliament ratified the accession treaty on Tuesday. Question: What will happen after the summit? Events: ['invited', 'join', 'finished', 'ratified', 'have', 'accession']

Answer: accession

Question: Passage: The two companies have recently agreed to extend their two existing contracts on purchasing Chinese electricity via the 110- kV power grid for the next four years, ensuring power supplies for the five Vietnamese provinces of Lao Cai, Lai Chau, Ha Giang, Yen Bai and Tuyen Quang. Vietnam has purchased 588 million kWh each year under the contracts since they were signed in 2004, said the report. Question: What happened before Vietnam began purchasing 588 million kWh per year? Events: ['agreed', 'extend', 'purchasing', 'ensuring', 'purchased', 'signed', 'said', 'report']

Answer:
signed