Given the task definition, example input & output, solve the new input case.
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.
Example: Passage: I submitted the hit. The hit was approved, and then I was paid. Question: What happened after I submitted the hit? Events: ['submitted', 'approved', 'paid'].
Output: approved, paid
From the passage, we can infer that events approved and paid happened after the event submitted. Therefore, the answer to this question is "approved, paid".

New input case for you: Passage: A terrorist expert said it was clear the IRA had embarked on a policy of causing maximum disruption and intimidation on the British mainland in the run-up to the general election on May 1. But neither Scotland Yard nor the organisers of Sunday's race would comment on whether security had been increased to take into account the IRA's apparent switch to targeting sporting events. Question: Wha began before the race and was still ongoing? Events: ['said', 'clear', 'embarked', 'policy', 'disruption', 'causing', 'intimidation', 'election', 'comment', 'increased', 'targeting', 'switch', 'race']
Output:
causing