How did barbed wire transform the lives of farmers on the Great Plains

How did barbed wire transform the lives of farmers on the Great Plains?

a. It allowed farmers to establish the boundaries of their farms, which previously had not been possible.
b. It made it possible for farmers to leave their farms for extended periods of time.
c. It helped farmers get cattle to northern markets along the cattle trails.
d. It kept Native Americans away from their farms so that their land was protected.
e. It allowed farmers to pen their animals and keep other animals off their land.

ANSWER
E