Open-range ranching came to an end due to a.) overproduction of beef and declining prices
b.) federal support for irrigated agriculture
c.) the range wars between cattlemen and sheepherders
d.) fencing off the plains with barbed wire
e.) increase in cattle production in the Midwest and East

This isn't for a class, it's for a project I'm doing outside of school with my friends.

D. fencing off the plains with barbed wire.

Explanation:

The great plains were fenced off with barbed wire, and I think it was mostly done in modern-day Texas, Oklahoma, Kansas, Nebraska, and the Dakotas.

Hope this helps! Feel free to give me Brainliest if you feel this helped. :)

answer: secession

secession, as it applies to the outbreak of the american civil war, comprises the series of events that began on december 20, 1860, and extended through june 8 of the next year when eleven states in the lower and upper south severed their ties with the union. the first seven seceding states of the lower south set up a provisional government at montgomery, alabama. after hostilities began at fort sumter in charleston harbor on april 12, 1861, the border states of virginia, arkansas, tennessee, and north carolina joined the new government, which then moved its capital to richmond, virginia. the union was thus divided approximately on geographic lines. twenty-one northern and border states retained the style and title of the united states, while the eleven slave states adopted the nomenclature of the confederate states of america.

explanation: