GMAT Sentence Correction (SC) | Re: Even their most ardent champions concede that no less than a

Even their most ardent champions concedethat 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)