Question: Which Montana county has a county seat with a population of 1,893 at the 2010 census?

Context paragraphs:
Gallatin County, Montana: Gallatin County is a county in the U.S. state of Montana.  As of the 2010 census, the population was 89,513, making it the third-most populous county in Montana.  Its county seat is Bozeman, home of Montana State University.  The county was founded in 1865.

Choteau, Montana: Choteau is a city in and the county seat of Teton County, Montana, United States.  It lies along U.S. Routes 89 and 287 (the latter terminating at the former in this city) about 20 mi east of the Rocky Mountains, near Flathead National Forest, the Rocky Mountain Division of Lewis and Clark National Forest, and Glacier National Park.  The population was 1,684 at the 2010 census.  The Montana town is named for French fur-trapper and explorer Pierre Chouteau, Jr., who is also the namesake of Chouteau County, Montana (county seat: Fort Benton).

Deer Lodge, Montana: Deer Lodge is a city in and the county seat of Powell County, Montana, United States.  The population was 3,111 at the 2010 census.  The city is perhaps best known as the home of the Montana State Prison, a major local employer.  The Montana State Hospital in Warm Springs, and former state tuberculosis sanitarium in nearby Galen are the result of the power the western part of the state held over Montana at statehood due to the copper and mineral wealth in that area.  Deer Lodge was also once an important railroad town, serving as a division headquarters for the Chicago, Milwaukee, St. Paul and Pacific Railroad ("the Milwaukee Road") before the railroad's local abandonment in 1980.

Columbus, Montana: Columbus is a town in and the county seat of Stillwater County, Montana, United States.  The population was 1,893 at the 2010 census.

Bozeman, Montana: Bozeman is a city in and the county seat of Gallatin County, Montana, United States, in the southwestern part of the state.  The 2010 census put Bozeman's population at 37,280 and by 2016 the population rose to 45,250, making it the fourth largest city in the state.  It is the principal city of the Bozeman, MT Micropolitan Statistical Area, consisting of all of Gallatin County with a population of 97,304.  It is the largest Micropolitan Statistical Area in Montana and is the third largest of all of Montana’s statistical areas.

Phillips County, Montana: Phillips County is a county located in the U.S. state of Montana.  As of the 2010 census, the population was 4,253.  Its county seat is Malta.  Before February 5, 1915, Phillips County was part of Blaine County, Montana, and before 1912 both were part of Chouteau County, Montana.  It was named in honor of rancher and state senator Benjamin D. Phillips.

Petroleum County, Montana: Petroleum County is a county located in the U.S. state of Montana.  As of the 2010 census, the population was 494, making it the least populous county in Montana and the seventh-least populous in the United States.  Its county seat is Winnett.  The Montana Legislature approved the formation of the county by separating it from Fergus County; Petroleum County was thus created on February 25, 1925, as the last of Montana's 56 counties.

Roosevelt County, Montana: Roosevelt County is a county located in the U.S. state of Montana.  As of the 2010 census, the population was 10,425.  Its county seat is Wolf Point.  Roosevelt County was created by the Montana Legislature in 1919 from Sheridan County.  The name honors former president Theodore Roosevelt, who had died shortly before the county was formed.

Great Falls, Montana: Great Falls is a city in and the county seat of Cascade County, Montana, United States.  The 2015 census estimate put the population at 59,638.  The population was 58,505 at the 2010 census.  It is the principal city of the Great Falls, Montana Metropolitan Statistical Area, which encompasses all of Cascade County and has a population of 82,278.  Great Falls was the largest city in Montana from 1950 to 1970, when Billings surpassed it.  Great Falls remained the second largest city in Montana until 2000, when it was passed by Missoula.  Since then Great Falls has been the third largest city in the state.

Stillwater County, Montana: Stillwater County is a county located in the U.S. state of Montana.  As of the 2010 census, the population was 9,117.  Its county seat is Columbus.

Supporting paragraphs: Stillwater County, Montana Columbus, Montana
Answer: Stillwater County, Montana