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
B it is .....
In D but one that ,does not refer to the principle but to the development zoes,,,,,,,,,,whereas in B "but one that" refers to principle folowed by was--singluar subject agreement!
i hate when people do'nt post the OA, it leaves in guessing!!!!