agree its an awkward but the god thng is it boils dwn to options A and B, rest all seem to suggest the zones themselves are the prciples.
it in A can refer to priciple or urban developmnt.
also B shows the contrast by using but. so went for b though it dorsnt sound good.
The proposed urban development zones do not represent a new principle; it was
employed in "Operation Bootstrap" in Puerto Rico.
(A) do not represent a new principle; it
(B) represent not a new principle, but one that
(C) are not a new principle; the same one
(D) are not a new principle, but one that
(E) are not new in principle; it
The only place where success comes before work is in the dictionary.
If my post made you think, KUDO it. Its easy :D