大全的一道题 求解啊

An attempt to ratify the Equal Rights Amendment, begun almost two decades ago, has been unsuccessful despite efforts by many important groups, including the National Organization for Women.

(A) to ratify the Equal Rights Amendment, begun almost two decades ago,
(B) begun almost two decades ago, for ratifying the Equal Rights Amendment
(C) begun for ratifying the Equal Rights Amendment almost two decades ago
(D) at ratifying the Equal Rights Amendment, begun almost two decades ago
(E) that has begun almost two decades ago to ratify the Equal Rights Amendment

答案是a,想不明白,xdjm帮帮忙啊,谢谢