标题: [大后天考]请教大全281题，在PP3上遇到了。 [打印本页] 作者: dxwei2008 时间: 2004-1-3 18:16 标题: [大后天考]请教大全281题，在PP3上遇到了。 281. Even their most ardent champions concede that no less than a technical or scientific breakthrough is necessary before solar cells can meet the goal of providing one percent of the nation’s energy needs.
(A) that no less than a technical or scientific breakthrough is necessary (B) that nothing other than a technical or scientific breakthrough is needed (C) that a technical or scientific breakthrough is necessary (D) the necessity for an occurrence of a technical or scientific breakthrough (E) the necessity for a technical or scientific breakthrough occurring