Many senior senators have created large staffs by means of

Many senior senators have created large staffs by means of their committee positions, while junior senators who want to be more active are forced to limp along with less aides than they need.
(A) while junior senators who want to be more active are forced to limp along with less aides than they need
(B) at the same time junior senators who want to be more active are forced to limp along with less aides than are necessary
(C) and junior senators who want to be more active are forced to limp along with less than the necessary number of aides
(D) while junior senators who want to be more active are forced to limp along with fewer aides than they need
(E) but junior senators who want to be more active are forced to limp along with their fewer than needed aides