(A) One half of the Greenvale Bank's tellers work full time, compared with Bosc Bank's two thirds and Community Bank, Farlo Bank, and Jantex Bank's three quarters.
Comparing GB's tellers with BB's two thirds and etc.
(B) One half of Greenvale Bank's tellers work full time, in Bosc Bank this number is two thirds, and in Community Bank, Farlo Bank, and Jantex Bank the number is three quarters.
The reference of "this number" is unclear.
(C) In Greenvale bank, one half of the tellers work full time, compared with two thirds in Bosc Bank and three quarters in Community Bank, Farlo Bank, and Jantex Bank.
Fits parallelism
(D) The fraction of tellers in Greenvale Bank who work full time is one half, compared with Bosc Bank's two thirds, Community Bank's three quarters, Farlo Bank's three quarters, and Jantex Bank's three quarters.
It would be more parallel if it was "two thirds in Bosc Bank", instead of "BB's two thirds".
(E) The fraction of Greenvale Bank's tellers working full time is one half, that of Bosc Bank is two thirds, and that of Community Bank, Farlo Bank, and Jantex Bank is three quarters.
It would be more parallel if it was "that of BB's tellers ...". Can't compare a fraction of GB's tellers with a fraction of a bank.