how did the invention of barbed wire transform the economy of the american west in the 1870s and 1880s

a. many factories emerged in the west to manufacture the wire, creating large numbers of jobs for new immigrants
b. the enclosure of the plains into farms and ranches ended the era of the great cattle drives from texas railroads in kansas and nebraska
c. cattle production declined because herds no longer had free rein over the praries
d. major meat-packing facilities moved from chicago and cincinnati to abilene and dodge city