Competition in the mid-nineteenth century by large western farms gradually caused farmers in Pennsylvania to turn to livestock raising, but before that it was predominantly grain-producing.

A. Competition in the mid-nineteenth century by large western farms gradually caused farmers in Pennsylvania to turn to livestock raising, but before that it was predominantly grain-producing.

B. Once predominantly a grain-producing state, competition in the mid-nineteenth century from large western farms gradually was causing Pennsylvania’s farmers to turn to livestock raising.

C. Pennsylvania’s farmers were gradually caused to turn to livestock raising by competition from large western farms in the mid-nineteenth century, but before that it was predominantly a grain-producing state.

D. It was once predominantly grain-producing, but competition in the mid-nineteenth century by large western farms was gradually causing Pennsylvania’s farmers to turn to livestock raising.

E. Pennsylvania was once a predominantly grain-producing state, but competition in the mid-nineteenth century from large western farms gradually caused the state’s farmers to turn to livestock raising.


OA is E, why A,B,C,D wrong???

In A, "it" refers to competition. It does not make sense.
In B, "Once predominantly a grain-producing state" modifies the noun (competition).
In C&D, it cannot modify noun in the possessive case (Pennsylvania’s).

I learn here "(preposition) + NOUN + VERBing is WRONG"

in choice E ,"to livestock raising" wont be wrong ? or i am missing something
OR
"livestock raising" is a noun


RON , please explain

Thank You

We need an original source for this question, please. :-)

_________________
Jamie Nelson
ManhattanGMAT Instructor