Answer:
I would probably say the final a for there are two.
Step-by-step explanation:
I say this for after John Brown had raided Harper's Ferry the fear of abolitionism began to grow even more in the south and the southern slave owners would obviously be afraid of more public outcry by the abolitionists. The Southern Militias would obviously be mobilized out of fear from those in charge. They would've drilled more in order to prevent rebellion to stop any further incidents that could possibly take place. For option C, Brown's Raid sparked the abolitionists to rather go to violent measures rather than peaceful to finally put an end to slavery and once he had been sent away to the gallows for his hanging after being charged guilty for being convicted for Treason, Murder and Conspiring with enslaved people to rebel and revolt. After he had died he became a martyr for his cause and was viewed as a revolutionary leader to Radical abolitionists.
If this isn't right I'm sorry I couldn't help, but its best to at least try.