문제 내용: 밑줄 친 부분과 의미가 가장 가까운 것은?
  Up to now, newspaper articles have only scratched the
  surface of this tremendously complex issue.
선택지 1: superficially dealt with
선택지 2: hit the nail on the head of
선택지 3: seized hold of
선택지 4: positively followed up on