Sentence Correction

Before they will consider a settlement, the
striking teachers demand that the school board
fire the substitute teachers and establishes
payment scales guaranteeing cost of living
increases.
(A) and establishes payment scales
guaranteeing cost of living increases
(B) and to establish payment scales that
would guarantee cost of living increases
(C) and establishes payment scales to
guarantee cost of living increases
(D) and establish payment scales to
guarantee cost of living increases
(E) to establish payment scales that would
guarantee cost of living increases


Wht is wrong with C.