Which option most accurately summarizes the conflicting perspectives that erupted into the conflict known as “bleeding kansas”?

Pro slavery advocates believed slave owners had a right to transport slaves into the territories; antislavery advocates argued that this gave slave holding settlers an unfair advantage over non-slave holding settlers.

Pro slavery advocates argued that the slave status of Kansas should be determined by popular vote; antislavery advocates argued that Kansas should be free because of its location north of the 36° 30' parallel.  

Pro slavery advocates contended that free African Americans in Kansas should not be permitted rights under the state constitution; antislavery advocates argued that the federal constitution took precedence over Kansas’s state constitution.

Pro slavery advocates held that slavery in the state was legal, as established in the Missouri Compromise of 1820; antislavery advocates argued that this legislation was invalidated by the Supreme Court’s ruling on the Dred Scott case.

Bleeding Kansas is the term used to described the period of violence during the settling of the Kansas territory. In 1854 the Kansas-Nebraksa Act overturned the Missouri Compromise’s use of latitude as the boundary between slave and free territory and instead, using the principle of popular sovereignty, decreed that the residents would determine whether the area became a free state or a slave state. Proslavery and free-state settlers flooded into Kansas to try to influence the decision. Violence soon erupted as both factions fought for control. Abolitionist John Brown led anti-slavery fighters in Kansas before his famed raid on Harpers Ferry.

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In October 1859, the U.S. military arsenal at Harpers Ferry was the target of an assault by an armed band of abolitionists led by John Brown (1800-59).

Explanation:

https://www.history.com/topics/abolotionist-movement/harpers-ferry