In the west, the combination of big business and new agricultural techniques resulted in
a. placer mines.
b. the long drive.
c. bonanza farms.
d. reservations.

the answer to fill in the blank in this question would be the word resource, it is defined as the money, material or people (since human resource is a very valuable good) that a company or a person has at disposition (meaning they can use the resource as they see fit), to be able to complete a task or achieve a goal.