Owners of large agricultural farms in the Southwest used to hire many extra workers to weed cotton fields. Then an amazing fact was discovered--that geese can accomplish the task better and cheaper than people. The weeds and grasses that are found in cotton fields are of the type that geese like to eat. The practice of farmers keeping large flocks of geese to weed fields is spreading rapidly. which best states the main idea of the paragraph?

Geese like weeds and grasses.
Weeds and grasses are used to fatten geese.
Cotton fields are located in the southwestern United States.
Geese replaced workers weeding cotton fields.