The correct answer is C) violence related to slavery.
In the 1850s, the term "Bleeding Kansas" referred to violence related to slavery.
The period of violence during the settling of the Kansas territory was known as "Bleeding Kansas." The Nebraska-Kansas Act of 1854 had changed the Missouri Compromise and now the residents would decide if the area become a free slave state or not. The violence generated by that decision between people that supported slavery and anti-slavery people was too much to the degree of coining the term "Bleeding Kansas."