Answer: A) proslavery settlers who came to Kansas from the neighbouring state of Missouri.
Border Ruffians were pro-slavery activist from Missouri (at the time, a slave state) that crossed the border into Kansas to force slavery there between 1854 and 1860.
The violence and attacks of the Ruffians are believed to have contributed to the beginning of the American Civil War. Although most of the Ruffians did not own slaves, they were motivated by patriotism and racism.
