20. (A), (B), (C) 각 네모 안에서 어법에 맞는 표현을 골라 짝지은 것으로 가장 적절한 것은?
No president since Franklin D. Roosevelt has held office for more than two terms. Roosevelt served four terms, and after his death during his last term in office, a law (A)restricted / restricting the number of terms a president could serve was passed. This was done because many people feared that an unscrupulous president would take advantage of a lengthy term to permanently install (B) him / himself in office. Today’s laws prevent a U.S. president (C) to be / from being elected more than two times.

어법문제인데 왜 저게 답인지 풀이부탁드려요. (본문 해석이 아니라 풀이!)

그리구 하나만더^^

This competition, teachers feel, [attracts / distracts] students from their school work.

에서 attracts 를 사용한다면 해석이 어떻게 되나요?