What was as remarkable as the development of the after-school enrichment programs has been New York City's nonprofit Chess-in-the-Schools initiative, giving more girls than ever before the opportunity to learn the rules of the game.

A.  What was as remarkable as the development of the after-school enrichment programs

B.  The thing that was as remarkable as developing the after-school enrichment programs

C.  No less remarkable than the development of the after-school enrichment programs

D.  Developing the after-school enrichment programs has been none the less remarkable than

E.  Development of the after-school enrichment programs has been no less remarkable as

The best answer is C. Besides being wordy, the beginnings of Choices A and B cause inconsistencies in verb tense: the development of the after-school programs cannot logically be described by both the present perfect and the past.  The phrases none the less… than in choice D and no less… as in E are unidiomatic.