Answer:
A. it led to a violent struggle over slavery in Kansas.
Step-by-step explanation:
The Kansas-Nebraska Act was a splendid failure.
Because it split up the Kansas and Nebraska territories and opened them up to popular sovereignty, meaning the inhabitants could choose to be slave or free state, people started pouring in to artificially raise the numbers in support of their political party and get a swing in Congress.
"Bleeding Kansas" followed soon after, with murders and violence at a high.